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Landscaping analysis of immunization progress and program structures in selected middle income Southeast Asian countries

Basa JE, Clemens R, Clemens SAC, Nicholson M

Vaccine, 2024 Apr 02;42(9):2326-2336.
PMID: 38448324 DOI: 10.1016/j.vaccine.2024.02.047

This study examined the performance and structures of national immunization program in five middle-income Southeast Asian countries - Malaysia, Thailand, Philippines, Viet Nam, and Myanmar, and analyzed how the different structures relate to the difference in program performance to identify effective strategies in the study countries that facilitated good immunization performance. Data were derived from published literature, and WHO/UNICEF/Gavi databases, with 2010 as the baseline year. UMICs Malaysia and Thailand maintained ≥90 % coverage from 2010 to 2020 and even during the COVID-19 pandemic in 2021. LMICs Viet Nam and donor-supported Myanmar also achieved 80-90 % coverage for most routine vaccines in 2020. The Philippines have not reached ≥90 % coverage since 2010, with the maximum only 72 % (MCV1 and Polio3) in 2020. All study countries prioritize immunization and increased government financing since 2010 by minimum 91 % in Malaysia and 1897 % in Myanmar. However, Myanmar still largely depended on donor support with government financing only 32 % of immunization costs in 2021. The Philippines funds 100 % of immunization costs and ensures sustainable financing for the NIP through earmarked "sin tax" revenues from alcohol and tobacco. Donor support influenced new vaccine introductions among the study countries, with Gavi countries Myanmar and Viet Nam introducing more new vaccines, compared to Gavi-ineligible Malaysia and Thailand. The Philippines reported vaccine stock-outs every year amounting to 28 stock-outs events from 2010 to 2019, compared to only 1-4 stockouts in the other study countries. Donor support, innovative financing, and domestic vaccine manufacturing all play an important role in the efficient delivery of immunization services as demonstrated by the several new vaccine introductions and high immunization rates in Myanmar though Gavi and UNICEF support, additional annual $1.2 billion budget for health and immunization from "sin taxes" in the Philippines, and lack of stockouts for vaccines sourced at affordable prices from domestic manufacturers in Viet Nam.
Immunogenicity of a recombinant Mycobacterium bovis bacille Calmette-Guèrin expressing malarial and tuberculosis epitopes

Rapeah S, Norazmi MN

Vaccine, 2006 Apr 24;24(17):3646-53.
PMID: 16494975 DOI: 10.1016/j.vaccine.2006.01.053

Recombinant Mycobacterium bovis bacille Calmette-Guèrin (rBCG) expressing the malarial epitopes F2R(II)EBA and (NANP)3 as well as two T cell epitopes of the M. tuberculosis ESAT-6 antigen, generated in favour of mycobacterium codon usage elicited specific immune response against these epitopes. Immunised Balb/c mice demonstrated an increase in almost all of the IgG subclasses against both malarial epitopes and enhanced splenocyte proliferative response against the malarial epitopes as well as selected peptides of ESAT-6. Furthermore, flow cytometric analyses showed elevated numbers of CD4+ lymphocytes expressing IFN-gamma and IL-2 against the ESAT-6 peptides, suggesting a specific Th1-mediated response. This study demonstrated that expressing malarial and TB epitopes in a single rBCG construct induced appropriate humoral and cellular immune response against immunogenic epitopes from both organisms.

Matched MeSH terms: BCG Vaccine/immunology*
Genetic and immunologic relationships between vaccine and field strains for vaccine selection of type A foot-and-mouth disease virus circulating in East Asia

Lee SY, Park ME, Kim RH, Ko MK, Lee KN, Kim SM, et al.

Vaccine, 2015 Jan 29;33(5):664-9.
PMID: 25528521 DOI: 10.1016/j.vaccine.2014.12.007

Of the seven known serotypes of foot-and-mouth disease virus (FMDV), type A has the most diverse variations. Genetic variations also occur frequently at VP1, VP2, VP3, and VP4 because these proteins constitute the viral capsid. The structural proteins of FMDV, which are closely related to immunologic correlations, are the most easily analyzed because they have highly accessible information. In this study we analyzed the type A vaccine viruses by alignment of available sequences in order to find appropriate vaccine strains. The matching rate of ASIA topotype-specific sites (20 amino acids) located on the viral surface, which are mainly VP1 and VP2, was highly related to immunologic reactivity. Among the available vaccines analyzed in this study, we suggest that A Malaysia 97 could be used as a vaccine virus as it has the highest genetic similarity and immunologic aspects to field strains originating in East Asia.
Repeated dose toxicity evaluation of a cold chain-free, live, attenuated oral cholera vaccine in Sprague Dawley rats

Xian TH, Parasuraman S, Sinniah K, Ravichandran M, Prabhakaran G

Vaccine, 2019 01 29;37(5):711-720.
PMID: 30630696 DOI: 10.1016/j.vaccine.2018.12.027

The repeated dose toxicity of a prototype cold chain-free, live, attenuated oral cholera vaccine containing 5 × 106 CFU/mL of the VCUSM14P strain was evaluated in Sprague Dawley (SD) rats (single dose administered daily for 30 days) to ascertain its safety for clinical use. Repeated dose toxicity studies for cholera vaccines in the literature have administered 2 or 3 fixed doses at 7, 14, 21 or 69 day intervals. The present study reports an evaluation of 30 repeated doses of cholera vaccine administered at three different concentrations (Group II (1.25 × 106 CFU), Group III (2.5 × 106 CFU) and Group IV (5 × 106 CFU)) in SD rats. The liquid vaccine was administered orally to the rats with the respective dose every day, and normal saline was administered to the control group (Group I). No significant difference (P > 0.05) was observed in the body weights and biochemical parameters of the rats after 15 and 30 repeated doses compared to those of the control group. However, compared to those of Group I, a significant increase (P 
Epidemiology and prevention of cervical cancer in Indonesia, Malaysia, the Philippines, Thailand and Vietnam

Domingo EJ, Noviani R, Noor MR, Ngelangel CA, Limpaphayom KK, Thuan TV, et al.

Vaccine, 2008 Aug 19;26 Suppl 12:M71-9.
PMID: 18945416 DOI: 10.1016/j.vaccine.2008.05.039

Cervical cancer remains one of the leading causes of cancers in women from Indonesia, Malaysia, the Philippines, Thailand and Vietnam. High-risk human papillomavirus (HPV) types, particularly HPV-16 and 18, are consistently identified in cervical cancer cases regardless of geographical region. Factors that have been identified to increase the likelihood of HPV exposure or subsequent development of cervical cancer include young age at first intercourse, high parity and multiple sexual partners. Cervical cancer screening programs in these countries include Pap smears, single visit approach utilizing visual inspection with acetic acid followed by cryotherapy, as well as screening with colposcopy. Uptake of screening remains low in all regions and is further compounded by the lack of basic knowledge women have regarding screening as an opportunity for the prevention of cervical cancer. Prophylactic HPV vaccination with the quadrivalent vaccine has already been approved for use in Malaysia, the Philippines and Thailand, while the bivalent vaccine has also been approved in the Philippines. However, there has been no national or government vaccination policy implemented in any of these countries.
A new MDCK suspension line cultivated in a fully defined medium in stirred-tank and wave bioreactor

Lohr V, Genzel Y, Behrendt I, Scharfenberg K, Reichl U

Vaccine, 2010 Aug 31;28(38):6256-64.
PMID: 20638458 DOI: 10.1016/j.vaccine.2010.07.004

An adherently growing MDCK cell line was adapted in a two-step process in a fully defined medium and in suspension. The resulting MDCK.SUS2 cells were subsequently evaluated for their potential as host cells for influenza vaccine production in two lab-scale bioreactors (wave and stirred-tank). Cell concentrations up to 2.3 x 10(6)cells/mL were obtained after 96 h, which is slightly higher than cell concentrations obtained with adherent MDCK cells cultivated on microcarriers (2g/L). Infections with influenza A/PR/8/34 and B/Malaysia resulted in high virus titers (2.90 and 2.75 log HA units/100 microL, respectively). The monitoring of extracellular metabolites, including amino acids, revealed a change in some of the metabolite consumption or release profiles, which indicates changes in metabolism during the adaptation process. Overall, the MDCK.SUS2 cell line represents a new cell substrate for a robust influenza vaccine production in a fully defined process.
Fulltext Hendra virus and Nipah virus animal vaccines

Broder CC, Weir DL, Reid PA

Vaccine, 2016 06 24;34(30):3525-34.
PMID: 27154393 DOI: 10.1016/j.vaccine.2016.03.075

Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures.
Cold adaptation improves the growth of seasonal influenza B vaccine viruses

Kim H, Schoofs P, Anderson DA, Tannock GA, Rockman SP

Vaccine, 2014 May 1;32(21):2474-9.
PMID: 24631096 DOI: 10.1016/j.vaccine.2014.02.079

Gene reassortment has proved useful in improving yields of influenza A antigens of egg-based inactivated vaccines, but similar approaches have been difficult with influenza B antigens. Current regulations for influenza vaccine seed viruses limit the number of egg passages and as a result resultant yields from influenza B vaccine seed viruses are frequently inconsistent. Therefore, reliable approaches to enhance yields of influenza B vaccine seed viruses are required for efficient vaccine manufacture. In the present study three stable cold-adapted (ca) mutants, caF, caM and caB derived from seasonal epidemic strains, B/Florida/4/2006, B/Malaysia/2506/2004 and B/Brisbane/60/2008 were prepared, which produced high hemagglutinin antigen yields and also increased viral yields of reassortants possessing the desired 6:2 gene constellation. The results demonstrate that consistent improvements in yields of influenza B viruses can be obtained by cold adaptation following extended passage. Taken together, the three ca viruses were shown to have potential as donor viruses for the preparation of high-yielding influenza B vaccine viruses by reassortment.
Fulltext Risk of serious adverse events after the BNT162b2, CoronaVac, and ChAdOx1 vaccines in Malaysia: A self-controlled case series study

Ab Rahman N, Lim MT, Lee FY, Lee SC, Ramli A, Saharudin SN, et al.

Vaccine, 2022 Jul 30;40(32):4394-4402.
PMID: 35667917 DOI: 10.1016/j.vaccine.2022.05.075

BACKGROUND: Rapid deployment of COVID-19 vaccines is challenging for safety surveillance, especially on adverse events of special interest (AESIs) that were not identified during the pre-licensure studies. This study evaluated the risk of hospitalisations for predefined diagnoses among the vaccinated population in Malaysia.
METHODS: Hospital admissions for selected diagnoses between 1 February 2021 and 30 September 2021 were linked to the national COVID-19 immunisation register. We conducted self-controlled case-series study by identifying individuals who received COVID-19 vaccine and diagnosis of thrombocytopenia, venous thromboembolism, myocardial infarction, myocarditis/pericarditis, arrhythmia, stroke, Bell's Palsy, and convulsion/seizure. The incidence of events was assessed in risk period of 21 days postvaccination relative to the control period. We used conditional Poisson regression to calculate the incidence rate ratio (IRR) and 95% confidence interval (CI) with adjustment for calendar period.
RESULTS: There was no increase in the risk for myocarditis/pericarditis, Bell's Palsy, stroke, and myocardial infarction in the 21 days following either dose of BNT162b2, CoronaVac, and ChAdOx1 vaccines. A small increased risk of venous thromboembolism (IRR 1.24; 95% CI 1.02, 1.49), arrhythmia (IRR 1.16, 95% CI 1.07, 1.26), and convulsion/seizure (IRR 1.26; 95% CI 1.07, 1.48) was observed among BNT162b2 recipients. No association between CoronaVac vaccine was found with all events except arrhythmia (IRR 1.15; 95% CI 1.01, 1.30). ChAdOx1 vaccine was associated with an increased risk of thrombocytopenia (IRR 2.67; 95% CI 1.21, 5.89) and venous thromboembolism (IRR 2.22; 95% CI 1.17, 4.21).
CONCLUSION: This study shows acceptable safety profiles of COVID-19 vaccines among recipients of BNT162b2, CoronaVac, and ChAdOx1 vaccines. This information can be used together with effectiveness data for risk-benefit analysis of the vaccination program. Further surveillance with more data is required to assess AESIs following COVID-19 vaccination in short- and long-term.
Challenges to health workers and their opinions about parents' refusal of oral polio vaccination in the Khyber Pakhtoon Khawa (KPK) province, Pakistan

Khan TM, Sahibzada MU

Vaccine, 2016 Apr 19;34(18):2074-81.
PMID: 26993330 DOI: 10.1016/j.vaccine.2016.03.008

A qualitative study design was adapted to explore the challenges faced by health workers (HWs) during the polio health campaign. In addition, HWs' opinions about the factors causing parents to refuse oral polio vaccination (OPV) were also explored. Four focus group discussions (FGDs) were held (from 1st January 2015-31st March 2015) with the HWs who participated in the OPV campaigns in the polio red zones of Khyber Pakhtoon Khawa (KPK) province of Pakistan, namely Kohat (FG 1), Domel and Bannu (FG 2), Hangoo (FG 3), and Peshawar (FG 4). A total of N=42 HWs (10-11 in each FG) agreed to participate in this study. Overall, HWs disclosed that public attitude and harsh behaviour towards the HWs and security threats are the two main challenges they face. Common issues hindering parents' willingness to vaccinate their children against OPV are: OPV is seen as haram and not permitted in Islam, it is said to contain the blood of pigs (Khinzir) and monkeys, and parents are afraid that it is done to induce sterility among their children. HWs also shared that parents have a strong belief in the conspiracies that are associated with OPV, i.e. the USA and CIA, are spying on us and our government is helping them to achieve their agenda. Furthermore, HWs revealed that frequent visits may further strengthen parents' perceptions and make them more resistant to OPV. The common side effects of OPV reported by parents were mainly gastro-intestinal problems and in some cases mild to moderate fever with some respiratory symptoms. There is a great need to improve the logistics and facilities for HWs assisting in vaccination programmes. Furthermore, it is necessary to improve education, so people understand the basic concept of revaccination and booster doses, thereby assisting in creating a basic understanding of vaccinations, which may trigger changes in attitudes and make people believe in the benefits of OPV rather than following the conspiracies that lead them to refuse it.

Matched MeSH terms: Poliovirus Vaccine, Oral/administration & dosage*
Factors influencing the uptake of 2009 H1N1 influenza vaccine in a multiethnic Asian population

Wong LP, Sam IC

Vaccine, 2010 Jun 17;28(28):4499-505.
PMID: 20451639 DOI: 10.1016/j.vaccine.2010.04.043

The study aimed to determine factors influencing the uptake of 2009 H1N1 influenza vaccine in a multiethnic Asian population. Population-based, cross-sectional survey was conducted between October and December 2009. Approximately 70% of overall participants indicated willingness to be vaccinated against the 2009 H1N1 influenza. Participants who indicated positive intention to vaccinate against 2009 H1N1 influenza were more likely to have favorable attitudes toward the 2009 H1N1 vaccine. A halal (acceptable to Muslims) vaccine was the main factor that determined Malay participants' decision to accept vaccination, whereas safety of the vaccine was the main factor that influenced vaccination decision for Chinese and Indian participants. The study highlights the challenges in promoting the 2009 H1N1 vaccine. Ethnic-sensitive efforts are needed to maximize acceptance of H1N1 vaccines in countries with diverse ethnic communities and religious practices.
Fulltext A randomized controlled phase 2 trial of the blood stage AMA1-C1/Alhydrogel malaria vaccine in children in Mali

Sagara I, Dicko A, Ellis RD, Fay MP, Diawara SI, Assadou MH, et al.

Vaccine, 2009 May 18;27(23):3090-8.
PMID: 19428923 DOI: 10.1016/j.vaccine.2009.03.014

A double blind, randomized, controlled Phase 2 clinical trial was conducted to assess the safety, immunogenicity, and biologic impact of the vaccine candidate Apical Membrane Antigen 1-Combination 1 (AMA1-C1), adjuvanted with Alhydrogel. Participants were healthy children 2-3 years old living in or near the village of Bancoumana, Mali. A total of 300 children received either the study vaccine or the comparator. No impact of vaccination was seen on the primary endpoint, the frequency of parasitemia measured as episodes >3000/microL/day at risk. There was a negative impact of vaccination on the hemoglobin level during clinical malaria, and mean incidence of hemoglobin <8.5 g/dL, in the direction of lower hemoglobin in the children who received AMA1-C1, although these differences were not significant after correction for multiple tests. These differences were not seen in the second year of transmission.
Fulltext Cost-effectiveness of dengue vaccination in ten endemic countries

Zeng W, Halasa-Rappel YA, Baurin N, Coudeville L, Shepard DS

Vaccine, 2018 01 08;36(3):413-420.
PMID: 29229427 DOI: 10.1016/j.vaccine.2017.11.064

Following publication of results from two phase-3 clinical trials in 10 countries or territories, endemic countries began licensing the first dengue vaccine in 2015. Using a published mathematical model, we evaluated the cost-effectiveness of dengue vaccination in populations similar to those at the trial sites in those same Latin American and Asian countries. Our main scenarios (30-year horizon, 80% coverage) entailed 3-dose routine vaccinations costing US$20/dose beginning at age 9, potentially supplemented by catch-up programs of 4- or 8-year cohorts. We obtained illness costs per case, dengue mortality, vaccine wastage, and vaccine administration costs from the literature. We estimated that routine vaccination would reduce yearly direct and indirect illness cost per capita by 22% (from US$10.51 to US$8.17) in the Latin American countries and by 23% (from US$5.78 to US$4.44) in the Asian countries. Using a health system perspective, the incremental cost-effectiveness ratio (ICER) averaged US$4,216/disability-adjusted life year (DALY) averted in the five Latin American countries (range: US$666/DALY in Puerto Rico to US$5,865/DALY in Mexico). In the five Asian countries, the ICER averaged US$3,751/DALY (range: US$1,935/DALY in Malaysia to US$5,101/DALY in the Philippines). From a health system perspective, the vaccine proved to be highly cost effective (ICER under one times the per capita GDP) in seven countries and cost effective (ICER 1-3 times the per capita GDP) in the remaining three countries. From a societal perspective, routine vaccination proved cost-saving in three countries. Including catch-up campaigns gave similar ICERs. Thus, this vaccine could have a favorable economic value in sites similar to those in the trials.
Fulltext Evaluation of BNT162b2 vaccine effectiveness in Malaysia: test negative case-control study

Lim AH, Ab Rahman N, Ong SM, Paraja J, Rashid R, Parmar IS, et al.

Vaccine, 2022 Sep 16;40(39):5675-5682.
PMID: 36030123 DOI: 10.1016/j.vaccine.2022.08.032

There is a notable lack of vaccine effectiveness studies using test-negative case-controlled approach in low- and middle-income countries which have different logistic, demographic and socio-economic conditions from high-income countries. We aimed to estimate the effectiveness of BNT162b2 vaccine against COVID-19 infection over time, intensive care unit admission, severe or critical disease and death due to COVID-19. This study was conducted in the resident population of Labuan aged ≥18 years who had been tested for SARS-CoV-2 by Reverse-Transcriptase Polymerase Chain Reaction between 1 March 2021 and 31 October 2021. We used a test-negative case-control design where 2644 pairs of cases and controls were matched by age, sex, testing date, nationality and testing reason. Analysis was stratified by age group to estimate age effect (<60 years and ≥60 years). Of 22217 individuals tested by Reverse-Transcriptase Polymerase Chain Reaction, 5100 were positive for SARS-CoV-2 and aged 18 years and above. Overall vaccine effectiveness ≥ 14 days after the second dose was 65.2% (95% CI: 59.8-69.9%) against COVID-19 infection, 92.5% (95% CI: 72.3-98.8%) against intensive care unit admission, and 96.5% (95% CI: 82.3-99.8%) against COVID-19 deaths. Among infected individuals, vaccine effectiveness was 79.2% (95% CI: 42.3-94.1%) in preventing severe or critical disease due to COVID-19. Vaccine effectiveness for ≥60 years was 72.3% (95% CI: 53.4-83.9%) in fully vaccinated individuals, higher than 64.8% (95% CI: 49.3-59.1%) for those <60 years. Two doses of BNT162b2 were highly effective against COVID-19 infection, severe or critical disease, intensive care unit admission and death due to COVID-19. This study addresses a gap in literature on BNT162b2 vaccine effectiveness in low- and middle-income populations and demonstrates the feasibility of such a study design in a resource limited setting while supporting evidence of waning immunity.
Identification of immunogenic proteins from Burkholderia cepacia secretome using proteomic analysis

Mariappan V, Vellasamy KM, Thimma JS, Hashim OH, Vadivelu J

Vaccine, 2010 Feb 3;28(5):1318-24.
PMID: 19944788 DOI: 10.1016/j.vaccine.2009.11.027

Burkholderia cepacia is an opportunistic human pathogen associated with lung infections. Secretory proteins of B. cepacia are known to be involved in virulence and may mediate important host-pathogen interactions. In the present study, secretory proteins isolated from B. cepacia culture supernatant were separated using two-dimensional gel electrophoresis, followed by Western blot analysis to identify the immunogenic proteins. Mice antibodies raised to B. cepacia inactivated whole bacteria, outer membrane protein and culture filtrate antigen detected 74, 104 and 32 immunogenic proteins, respectively. Eighteen of these immunogenic proteins which reacted with all three antibodies were identified and might be potential molecules as a diagnostic marker or a putative candidate vaccine against B. cepacia infections.
Immunogenicity and tolerability of a virosome influenza vaccine compared to split influenza vaccine in patients with sickle cell anemia

Souza AR, Braga JA, de Paiva TM, Loggetto SR, Azevedo RS, Weckx LY

Vaccine, 2010 Jan 22;28(4):1117-20.
PMID: 20116631 DOI: 10.1016/j.vaccine.2009.05.046

The immunogenicity and tolerability of virosome and of split influenza vaccines in patients with sickle cell anemia (SS) were evaluated. Ninety SS patients from 8 to 34 years old were randomly assigned to receive either virosome (n=43) or split vaccine (n=47). Two blood samples were collected, one before and one 4-6 weeks after vaccination. Antibodies against viral strains (2006) A/New Caledonia (H1N1), A/California (H3N2), B/Malaysia were determined using the hemagglutinin inhibition test. Post-vaccine reactions were recorded over 7 days. Seroconversion rates for H1N1, H3N2 and B were 65.1%, 60.4% and 83.7% for virosome vaccine, and 68.0%, 61.7% and 68.0% for split vaccine. Seroprotection rates for H1N1, H3N2 e B were 100%, 97.6% and 69.7% for virosome, and 97.8%, 97.8% and 76.6% for split vaccine. No severe adverse reactions were recorded. Virosome and split vaccines in patients with sickle cell anemia were equally immunogenic, with high seroconversion and seroprotection rates. Both vaccines were well tolerated.
Fulltext Protection against henipaviruses in swine requires both, cell-mediated and humoral immune response

Pickering BS, Hardham JM, Smith G, Weingartl ET, Dominowski PJ, Foss DL, et al.

Vaccine, 2016 09 14;34(40):4777-86.
PMID: 27544586 DOI: 10.1016/j.vaccine.2016.08.028

Hendra virus (HeV) and Nipah virus (NiV) are members of the genus Henipavirus, within the family Paramyxoviridae. Nipah virus has caused outbreaks of human disease in Bangladesh, Malaysia, Singapore, India and Philippines, in addition to a large outbreak in swine in Malaysia in 1998/1999. Recently, NiV was suspected to be a causative agent of an outbreak in horses in 2014 in the Philippines, while HeV has caused multiple human and equine outbreaks in Australia since 1994. A swine vaccine able to prevent shedding of infectious virus is of veterinary and human health importance, and correlates of protection against henipavirus infection in swine need to be better understood. In the present study, three groups of animals were employed. Pigs vaccinated with adjuvanted recombinant soluble HeV G protein (sGHEV) and challenged with HeV, developed antibody levels considered to be protective prior to the challenge (titers of 320). However, activation of the cell-mediated immune response was not detected, and the animals were only partially protected against challenge with 5×10(5) PFU of HeV per animal. In the second group, cross-neutralizing antibody levels against NiV in the sGHEV vaccinated animals did not reach protective levels, and with no activation of cellular immune memory, these animals were not protected against NiV. Only pigs orally infected with 5×10(4) PFU of NiV per animal were protected against nasal challenge with 5×10(5) PFU of NiV per animal. This group of pigs developed protective antibody levels, as well as cell-mediated immune memory. Peripheral blood mononuclear cells restimulated with UV-inactivated NiV upregulated IFN-gamma, IL-10 and the CD25 activation marker on CD4(+)CD8(+) T memory helper cells and to lesser extent on CD4(-)CD8(+) T cells. In conclusion, both humoral and cellular immune responses were required for protection of swine against henipaviruses.
Fulltext A Malaysia 97 monovalent foot-and-mouth disease vaccine (>6PD50/dose) protects pigs against challenge with a variant FMDV A SEA-97 lineage virus, 4 and 7 days post vaccination

Nagendrakumar SB, Hong NT, Geoffrey FT, Jacqueline MM, Andrew D, Michelle G, et al.

Vaccine, 2015 Aug 26;33(36):4513-9.
PMID: 26192355 DOI: 10.1016/j.vaccine.2015.07.014

Pigs play a significant role during outbreaks of foot-and-mouth disease (FMD) due to their ability to amplify the virus. It is therefore essential to determine what role vaccination could play to prevent clinical disease and lower virus excretion into the environment. In this study we investigated the efficacy of the double oil emulsion A Malaysia 97 vaccine (>6PD50/dose) against heterologous challenge with an isolate belonging to the A SEA-97 lineage at 4 and 7 days post vaccination (dpv). In addition, we determined whether physical separation of pigs in the same room could prevent virus transmission. Statistically there was no difference in the level of protection offered by 4 and 7 dpv. However, no clinical disease or viral RNA was detected in the blood of pigs challenged 4 dpv, although three of the pigs had antibodies to the non-structural proteins (NSPs), indicating viral replication. Viral RNA was also detected in nasal and saliva swabs, but on very few occasions. Two of the pigs vaccinated seven days prior to challenge had vesicles distal from the injection site, but on the inoculated foot, and two pigs had viral RNA detected in the blood. One pig sero-converted to the NSPs. In contrast, all unvaccinated and inoculated pigs had evidence of infection. No infection occurred in any of the susceptible pigs in the same room, but separated from the infected pigs, indicating that strict biosecurity measures were sufficient under these experimental conditions to prevent virus transmission. However, viral RNA was detected in the nasal swabs of one group of pigs, but apparently not at sufficient levels to cause clinical disease. Vaccination led to a significant decrease in viral RNA in vaccinated pigs compared to unvaccinated and infected pigs, even with this heterologous challenge, and could therefore be considered as a control option during outbreaks.
HPV information needs, educational messages and channel of delivery preferences: views from developing country with multiethnic populations

Wong LP

Vaccine, 2009 Feb 25;27(9):1410-5.
PMID: 19150379 DOI: 10.1016/j.vaccine.2008.12.045

This qualitative study used focus group discussions (FGDs) to evaluate information needed in order to make informed human papillomavirus (HPV) vaccination decision, opinion on the most acceptable public education messages, and channel of delivery in a multiethnic, multicultural and multireligion country. A total of 19 FGDs were conducted among mothers of eligible vaccinees, young women eligible for the vaccine, and men. Messages that carry accurate information about HPV-cervical cancer link, the HPV preventive vaccines and at the same time minimize the stigma of a sexually transmitted infection (STI) vaccine were preferred. Educational messages for future HPV educational intervention were developed and methods to effectively convey to the public the need for HPV vaccination were identified. The findings serve as a basis for future intervention to develop research-based communication materials and strategies.
Physicians' experiences with HPV vaccine delivery: evidence from developing country with multiethnic populations

Wong LP

Vaccine, 2009 Mar 4;27(10):1622-7.
PMID: 19100803 DOI: 10.1016/j.vaccine.2008.11.107

Physicians' experiences in providing human papillomavirus (HPV) immunization were assessed by mailed questionnaire. Response rate of 41.4% was achieved. Malay Muslim physicians were more likely to agree that cultural sensitivity is an issue when recommending HPV vaccines. Pediatricians and family physicians were more likely to agree that acceptance is better if vaccines were recommended to prevent cervical cancer than to prevent a sexually transmitted disease. Near 70% rated success of HPV vaccines recommendation in their practice as very poor with the majority patients preferred to postpone immunization. Physicians reported cultural disparities in vaccine uptake and perceived high vaccination cost limits its use.

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