A case of double infection with Brugia pahangi and Dirofilaria immitis in a clouded leopard, Neofelis nebulosa, is presented. A brief review of filarial infections in both man and wild animals, and their medical importance is discussed.
The susceptibility of Culex sitiens to Japanese Encephalitis (JE) virus was examined in the laboratory. Cx. sitiens became infected with JE virus on day 8 and subsequently it is able to transmit the virus when it takes a blood meal. Both parts of the experiment were carried out using artificial membrane feeding technique.
Oxyspiruriasis caused by the bird eyeworm, Oxyspirura mansoni, a thelaziid nematode, in three species of pheasants, 3 Chrysolophus pictus (golden pheasant), 7 Lophura nycthemera (silver pheasant) and 9 Phasianus colchicus (common pheasant) in Zoo Negara Malaysia are reported. Birds with the disease were treated with a solution of 0.5% iodine or 0.5% lysol. Antistress powder for 4 days in water and non-strep vitamin powder in water was also provided. Control measures included removal of the cockroach intermediate host, Pycnoscelus surinamensis (Surinam cockroach) from the vicinity of the birds. The golden pheasant is a new host for O. mansoni in peninsular Malaysia.
Rodents were collected from five wet markets (Chow Kit, Dato Keramat, Setapak, Jinjang and Kepong) in Kuala Lumpur, Federal Territory between March to April 2006. Ninety seven rats were trapped using wire traps measuring 29 x 22 x 50 cm baited with fruits, coconuts, dried fish or sweet potatoes. A total of 17 different species of parasites were identified from three species of rats out of which 11 (65%) were identified to be zoonotic. The helminths identified from the urban rats were nematodes- Capillaria hepatica, Gongylonema neoplasticum, Heterakis spumosa, Heterakis sp., Masterphorus muris, Nippostrongylus brasiliensis, Physolaptera sp., Pterogodermatis sp., Rictularia tani and Syphacia muris; cestodes- Hymenolepis nana, Hymenolepis diminuta, Hymenolepis sabnema, Hymenolepis sp., Raillietina sp. and Taenia taeniaeformis, and acanthocephalan- Moniliformis moniliformis. The following parasites are of potential medical importance: C. hepatica, G. neoplasticum, R. tani, S. muris, H. diminuta, H. nana, Raillietina sp. and T. taeniaeformis.
A total of 204 rodents comprising 14 host species from four different habitats were examined. Nine rodent species were trapped from the forest and another five species were trapped from the coastal, rice field and urban habitats. Rattus rattus diardii (67%) was the predominant rodent species examined. Fifty six (47.3%) rodents and shrews were found to be infested with at least one of the 20 species of ectoparasite recovered. Mites belonging to the family Trombiculidae were the predominant ectoparasite species recovered. Ticks belonging to the family Ixodidae were recovered mainly from the forest dwelling rodents. Polyplax spinulosa and Hoplopleura pacifica were the common lice species found infesting the urban rodents. Xenopsylla cheopis was the only flea species recovered. The following ecto-parasites have been incriminated as important vectors or as mechanical carriers for the transmission of zoonotic diseases: Ixodes granulatus, Dermacentor sp. Haemaphysalis sp., Amblyomma sp. Ascoschoengastia indica, Leptotrombidium deliense, Ornithonyssus bacoti, Laelaps nuttalli, H. pacifica, P. spinulosa and Xenopsylla cheopis. Urban and forest rodents were significantly higher in ecto-parasitic infestation, compared to rats from the other two habitats. However, there was no significant statistical association between male and female rodents infested with ectoparasites.
A survey for small mammal parasites carried out in a secondary forest of Ulu Gombak, Selangor, Peninsula Malaysia yielded the following animals: Rattus bowersi (7), Rattus tiomanicus jalorensis (2), Maxomys rajah (12), Maxoyms whiteheadi (3), Leopoldamys sabanus(13), Sundamys muelleri(10), Lariscus insignis (1), Sundasciurus tenuis (1) and Tupaia glis (2). The following nematodes: Capillaria hepatica, Hepatojarakus malayae, Trichostrongylus sp. and Streptopharagus sp., the following cestodes: Hymenolepis sp., Raillietina sp. and Taenia taeniaformis; and trematode, Zonorchis sp. from Tupaia glis were recovered. No parasites were observed during blood examination. No endoparasite was seen in Maxomys whiteheadi, Lariscus insignis and Sundasciurus tenuis. The following parasites, Capillaria hepatica, Hymenolepis sp., Raillietina sp. and Taenia taeniaformis are considered of medical importance.
There were a spate of recent complaints of insect bites and the entomological specimens received from various sources were identified to be those of cat flea (Ctenocephalides felis) and rat flea (Xenopsylla cheopis), the tropical bed-bug (Cimex hemipterus) and the dog louse (Heterodoxus spiniger). Only the fleas and the bed-bug are known to attack humans.
Forensic entomological specimens received by the Unit of Medical Entomology, IMR., from hospitals and the police in Malaysia in the last 3 decades (1972 - 2002) are reviewed. A total of 448 specimens were received. From these, 538 identifications were made with the following results: Eighteen species of cyclorrphaga flies were identified consisting of Chrysomya megacephala (Fabricius) 215 cases (47.99%), Ch. rufifacies (Masquart) 132 (29.46%), Ch. villeneuvi Patton 10 (2.23%), Ch. nigripes Aubertin 7 (1.56%), Ch. bezziana Villeneuve 4 (0.89%), Ch. pinguis (Walker) 1 (0.22%), Chrysomya sp. 47 (10.49%), Sarcophaga sp. 28 (6.25%), Lucilia sp. 21 (4.69%), Hermetia sp. 15 (3.35%), He. illucens (Linnaeus) 1 (0.22%), Hemipyrellia ligurriens (Wiedemann) 3 (0.67%), Hemipyrellia sp. 2 (0.45%), Ophyra spinigera 1 (0.22%), Ophyra sp. 6 (1.34%), Calliphora sp. 24 (5.36%), Synthesiomyia nudiseta (Wulp) 1 (0.22%) and Eristalis sp. 1 (0.22%). Other non - fly insect specimens are Pthirus pubis (Linnaeus) (Pubic louse) 2 (0.45%) and Coleoptera (Beetles) 1 (0.22%). Ch. megacephala and Ch. rufifacies were the commonest species found in cadavers from different ecological habitats. Sy. nudiseta is an uncommon species, thus far found only on cadavers from indoors. Sy. nudiseta is reported for the second time in Peninsular Malaysia. A total of 329 cases (73.44%) had a single fly infestation, 109 cases (24.33%) had double fly infestation and 10 cases (2.23%) had triple fly infestation. Five cases (1.12%) had eggs and 3 cases (0.67%) had larval stages that were not identifiable. No arthropods were retrieved from cadavers in 8 cases (1.79%). In conclusion, although large number of fly species were found on human cadavers, the predominant species are still those of Chrysomya.
The hornets are a group of venomous stinging insects that at times cause human death. A fatal case of a child stung by the lesser banded hornet Vespa affinis indosinesis is reported. Though often covered by the mass media, this constitutes the first scientifically reported case.
Unidentified mermithid nematodes were found in the abdominal cavity of three species of Anopheles mosquitoes from LAO PDR. This is a first record of mermithid nematodes in adult mosquitoes from Lao PDR. Two worms were found in each adult host and the infection was more prevalent in the northern region compared to the south.
A total of 1,157 sera from jaundiced patients with clinical and biochemical evidence of liver disease received from government hospital in Kelantan and Terengganu, during the period from 1994 to 1997, were investigated to determine the cause. Hepatitis A virus was found to be the main cause in 26.1% (24/92) of symptomatic clinical hepatitis cases in 1994, 47.8% (63/132) in 1995, 66.4% (613/923) in 1996 and 20% (2/10) in 1997. Sera received in 1996 were also tested for hepatitis B, hepatitis C, hepatitis D and hepatitis E. 1.4% (13/923) anti-bodies were found to be positive for HBc IgM indicating recent HBV infection, 5.4% (50/923) for total HCV Ab, 0.9% (8/923) for total HDV Ab and 0.4% (4/923) for anti-HEV IgM. This study shows that HAV is still a major problem in Kelantan and Terengganu, and there is a need to identify effective strategies for prevention and control in these two states.
Surveillance studies on cercarial dermatitis were carried out in paddy growing areas in Peninsular Malaysia. It was observed that dermatitis in paddy planters occurred in paddy fields which were cultivated using animals such as bafflos or fields where domestic animals were allowed to graze during the off planting season as these animals harbored the parasite. The causative agent of cercarial dermatitis was Schistosoma spindale. A total of 215 small mammals trapped from Alor Setar and 126 trapped from Labu were examined for the schistosome. In Alor Setar Bandicota indica, Rattus argentiventer and Rattus rattus diardii were the only wild mammals found to be infected with the parasite, while in the Labu areas only Rattus tiomanicus jalorensis was positive for the schistosome. The occurrence of S. spindale in R. argentiventer and R.r. diardii in Alor Setar and in R.t. jalorensis in Labu constitute new host and geographic distribution records of the schistosome.
The Aborigines or Orang Asli in Peninsular Malaysia who are still seminomadic are known to have a close association with dogs. In this study, enzyme-linked immunosorbent assay (ELISA) was used to detect anti-Sarcoptes scabiei var canis antibodies in this community as a measure of exposure to the mite. Out of 312 Orang Asli tested, 24.7% were positive for polyvalent anti-Sarcoptes antibodies. No significant difference was found between the positive rates in males (26.1%) and females (23.6%). Only 1.9% were positive for IgA and none was positive for IgE anti-Sarcoptes antibodies. Since there were very few patients with clinical manifestation of scabies, there is a possibility that continuous exposure to the dogs mite confers cross-protective immunity in the community against human scabies.
The occurrence of adult Gnathostoma malaysiae in Rattus surifer and R. tiomanicus in Malaysia has been reported but there are no known reports on the host tissue reactions. This paper reports on the gross pathology caused by G. malaysiae in a red spiny forest rat, R. surifer and the tissue reactions caused. A tumor-like growth was located on the mid-stomach wall in a female rat captured in Gunung Bachock, Kelantan, Malaysia. This growth consisted of four tunnel-like structures containing sanguinopurulent fluid and leukocytes and this structure led into a central canal. The tissue surrounding the tumor was greatly inflamed and there was localized gastritis. The tunnel-like structure was surrounded by dense fibrotic tissue. The stomach wall was devoid of superficial epithelium and smooth muscle but mucinous glands were present. The midregion of the fibrotic scar contained eggs of G. malaysiae which had evoked a strong tissue reaction and were surrounded by pus. Blood vessels were empty, dilated and had undergone vasculitis and thrombosis.
One hundred and fifty one house rats, Rattus rattus diardii from five different localities, Jinjang, Dato Keramat, Kuala Lumpur, Sungai Besi and Selayang Baru, were examined for parasites. Nineteen species of parasites were recovered. Hymenolepis diminuta and Nippostrongylus brasiliensis are the predominant species. The dominancy of the parasite species in the rats differed in each locality: Hymenolepis diminuta in Dato Keramat and Kuala Lumpur; Nippostrongylus brasiliensis in Sungai Besi; Gongylomena neoplasticum in Jinjang and Selayang Baru. The influences of human habitats on the parasite fauna of house rats are discussed.