The twenty-first century has witnessed some of the deadliest viral pandemics with far-reaching consequences. These include the Human Immunodeficiency Virus (HIV) (1981), Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) (2002), Influenza A virus subtype H1N1 (A/H1N1) (2009), Middle East Respiratory Syndrome Coronavirus (MERS-CoV) (2012) and Ebola virus (2013) and the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) (2019-present). Age- and gender-based characterizations suggest that SARS-CoV-2 resembles SARS-CoV and MERS-CoV with regard tohigher fatality rates in males, and in the older population with comorbidities. The invasion-mechanism of SARS-CoV-2 and SARS-CoV, involves binding of its spike protein with angiotensin-converting enzyme 2 (ACE2) receptors; MERS-CoV utilizes dipeptidyl peptidase 4 (DPP4), whereas H1N1 influenza is equipped with hemagglutinin protein. The viral infections-mediated immunomodulation, and progressive inflammatory state may affect the functions of several other organs. Although no effective commercial vaccine is available for any of the viruses, those against SARS-CoV-2 are being developed at an unprecedented speed. Until now, only Pfizer/BioNTech's vaccine has received temporary authorization from the UK Medicines and Healthcare products Regulatory Agency. Given the frequent emergence of viral pandemics in the 21st century, proper understanding of their characteristics and modes of action are essential to address the immediate and long-term health consequences.
Microbial diseases continue to occur in Malaysia despite the marked socio-economic development that has been taking place in the country along with improvements in the medical, health, and environmental sectors. This paper highlights the continuing presence of the numerous microbial diseases including the emergence of new problems such as AIDS. Local publications dealing with work on several microbial diseases is reviewed to show that this group of diseases will pose challenges for a long while. Undoubtedly several other diseases that were relatively unrecognised in the past are increasingly being identified owing to recent availability of diagnostic facilities and equipments. The need for continued vigilance is emphasised.
Viral infections are probably the most important cause of childhood morbidity and mortality in the world. In many developing countries in South East Asia and the Western Pacific, priority health problems include acute respiratory infections, acute diarrhoeas and arboviral infections. Where studies have been carried out, there is no significant difference in the aetiological agents involved or in the manifestation of clinical childhood disease. Surveillance of these diseases have improved with the introduction of rapid viral diagnosis. The better understanding of the immunopathogenesis of many diseases have also encouraged research in this area and will lead to the better control and management of these diseases. However, the search for antivirals has been disappointing but fortunately new vaccines are on the horizon and the prospect for bringing some of these diseases under control through vaccination are bright.