key: cord-0039002-yvhsxzzs
authors: nan
title: PL2 Emerging viral diseases in Asia: Deciphering the writing on the wall
date: 2005-11-12
journal: Int J Antimicrob Agents
DOI: 10.1016/s0924-8579(05)80003-2
sha: 9a15f0163c471f7386c6425c145182afccd69faa
doc_id: 39002
cord_uid: yvhsxzzs

nan

The wonder years of the antimicrobial era appear to be over. The burden of resistance is reaching a "'crisis" and the pace of discovery has slowed. We need new drugs, vaccines, rapid diagnostic methods and to husband the current drugs. There needs to be greater emphasis on appropriate use, dampening of scare tactics by media and promotion by the pharmaceutical industry. Charles Darwin foresaw these evolutionary events in 1859 in the "'On the Origin of Species by Natural Selection". Paul Ehrlich, the Father of Chemotherapy in his 1908 Nobel Lecture, described trypanosomes that became multiply resistant to arsenicals and emergence of resistance during therapy. Alexander Fleming, in his 1945 Nobel Lecture, warned about development of resistance from over-the-counter purchase of penicillin.

Fleming wrote: "'Penicillin is ... non-poisonous so there is no need to worry about ... an overdose .... There may be a danger ... in underdosage. It is not difficult to make microbes resistant to penicillin ... by exposing them to concentrations not sufficient to kill them ... The time may come when penicillin can be bought by anyone in the shops. Then there is the danger that the ignorant man may ... underdose himself and by exposing his microbes to non-lethal quantities ... make them resistant. Here is a hypothetical illustration. Mr. X. has a sore throat. He buys some penicillin and gives himself, not enough to kill the streptococci but enough to ... resist penicillin. He then infects his wife. Mrs. X gets pneumonia and is treated with penicillin. As the streptococci are now resistant to penicillin the treatment fails. Mrs. X dies. Who is primarily responsible for Mrs. X's death? Moral: If you use penicillin, use enough.'" Fleming was remarkably prescient. In the 1950s Ernest Jawetz ( The crisis of resistance finally became evident to policy-making organizations during the last decade. Finally, in 1999 the CDC became the lead organization to develop a public health plan to combat antimicrobial resistance. It developed an excellent 12 step action plan. The WHO also published a well-reasoned Global Strategy for Containment of Antibiotic Resistance in 2001. The message has finally gotten through.

The challenges for the future include the need to: discover new antimicrobial drugs and virulence inhibitors, further develop effective vaccines for community and hospital-acquired infections, devise in expensive rapid diagnostic tests that can be used in offices and at the bedside, and implement the WHO and CDC guidelines in the community and hospitals worldwide. The most difficult task will be to decrease casual use of antibiotics. The torch has been passed to a new generation. Are you willing to accept this responsibility?

Infectious diseases account for more than 17 million deaths worldwide each year and up to half the world's population are at risk for many endemic diseases. Respiratory and diarrheal infections due to bacteria and viruses kill almost 7 million children each year, mostly in developing countries, despite the fact that vaccines and antibiotics axe available [1] . The re-emergence and increasing importance of diseases such as tuberculosis, hand-foot-mouth disease (HFMD), HIV/AIDS, viral hepatitis and dengue in Southeast Asia has posed public major health problems. In addition, the recent emergence of novel viruses such as Nipah, SARS coronavirus and avian influenT~ has focused attention on the region as an epicenter for potential global pandemics.

Many factors favor the emergence and re-emergence of infectious diseases particularly in Asia [2] . Climatic changes such as E1 Nino create an ideal environment for vector-borne diseases such as dengue and Japanese encephalitis. Outbreaks of dengue have become larger and more severe and the 2004 outbreak in Indonesia resulted in 700 deaths. Despite intensive control measures being implemented, it is unlikely that dengue can be successfully controlled. Even in Singapore with its stricter control measures, the dengue situation last year was the worst in the last decade. In Malaysia, an outbreak of chikungunya polyaxthritis was thought to be due to the importation of the virus by migrant workers and the disease has become endemic due to the abundance of Aedes aegspti mosquitoes [3] . It is also generally feared that yellow fever virus, which shares the same vector as dengue, may inadvertently be introduced to the region through expanding tourism and trade with yellow fever endemic countries.

For economic reasons, countries in the region have depended on natural resources for their needs. Deforestation for logging, opening land for agriculture and the building of dams have exposed humans to exotic microorganisms and can lead to new infectious diseases. The promotion of eco-tourism in tropical countries such as Malaysia has already resulted in an outbreak of leptospirosis among participants from several countries. Emerging diseases that involve livestock such as avian influenza and Nipah infections have resulted in severe economic loss. Delay in reporting such outbreaks and the lack of transparency for fear of trade sanction will make 0924-8579/$ -see front matter © 2005 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Speakers' Abs:raets / Imernational Journal of Antimicrobial Agents 26S (2005) S1 S6J the situation worse. The low compensation given for each culled animal is also a disincentive for reporting.

Population increase and rural urban migration in Asia will continue to tax a country's infrastructure for clean water supply and sanitation, resulting in the potential for outbreaks. Heavy dependency on migrant workers in some countries will add to the burden of sexually transmitted diseases, HIV/AIDS and viral hepatitis [4] . The increasing spread of HIV is attributed to intravenous drug use and sexual promiscuity. Due to cultural and religious sensitivities, control programmes involving needle exchange, sex education and condom usage are not actively promoted. The easy access to prescription drugs including antibiotics and the lack of antibiotic policy have led to resistant strains of bacteria such as methicillin-msistant Staphylococcus aureus (MRSA). The use of antibiotics in farm feeds is yet another contributory factor to bacteria resistance. Generally, good farming practice is the exception rather than the norm in the region. Intense mixed fanning has created an environment that allows inter species exchange of genetic materials. Backyard famls mid flee-range domestic animals such as chicken, ducks and pigs are common in Asia, further adding to the problem. The preference for freshly slaugfiteied poulti% the keeping of fighting cocks and the gastronomic delight in exotic meats have posed many problems in the control of avian influenza.

The fear of influenza H5N1 pandemic is justified. There is already evidence that the virus can jump species, not only from chicken to humans but to tigers and cats as well [5] . The infection of ducks can lead to asymptomatic infection and results in prolonged excretion of the virus. The recent evidence of human-to-human spread and asymptomatic human cases will add to this fear. HSN1 virus has developed resistance to amantadine and rimantadine through genetic changes and we are left with only limited antivirals such as oseltamivir, which are not only expensive for developing countries but also limited in supply. The difficulty of preparing an inactivated H5N1 vaccine using traditional methods has led to delay and the production of a pandemic influenza vaccine using reverse genetics are tied up with the question of intellectual property and indemnity.

The convergence of many factors will lead to emerging and reemerging diseases in Asia and the writing is on the wall. The global alert for im pending pandemic influenza is therefore most relevant to Asian countries. The Wodd Health Organization has issued repeated warnings and urged all member countries to have contingency plans of preparedness in place.

Developing countries in the region do not have sufficient surge capacity to handle outbreaks of emerging diseases. During the Nipah virus outbreak in Malaysia, there were insufficient beds, ventilators and health care workers in government run hospitals and in the SARS outbreak in 2004; it was also evident that many countries could not cope with the situation. With influenza, it is expected that there will be millions of severe cases and deaths, which will tax the reanulves even further.

Besides avian influenza and SARS, there is mounting evidence that several viral diseases are ready to take off and spread far and wide. The rapid spread of West Nile virus across USA and the spread of Nipah virus to Bangladesh are early warnings of things to come. The spread of SARS from one isolated case in Hong Kong exemplified the role of rapid mass transportation in emerging diseases. The enterovirus 71 HFMD outbreak in Malaysia resulted in the death of over 40 young children and the following year, the virus was found to be responsible for a large outbreak in Taiwan.

Intense surveillance and research are important in the ongoing fight against emerging diseases with the potential for global pandemics. Since Asia is the epicenter of these diseases, it is imperative that continuous resoumes should be made available to fight and control the outbreak at source. As for reseamh, it is regrettable that no BSL 4 laboratory is readily available and such research has to be outsoureed to developed countries with such facilities. During the recent ASEAN+3 Expert Group Meeting on Emerging Diseases, the Asia Pacific Society for Medical Virology recommended the establishment of an ASEAN Centre for Disease Control (ACDC) with BSL 4 facility. This will allow regional scientists to conduct research collaboratively at an affordable cost on pathogens such as Nipah, avian influenza H5N1 and SARS isolated in the region. Also recommended is for greater use of regional experts in outbreak investigations such as dengue, HIV/AIDS, influenza, viral hepatitis, enterovirus 71 and Nipah. Through such collaboration and sharing of resources, it is predicted that, in the foreseeable future, the Asian region will be able to throw away its crutches and become self reliant.

The world is facing a frightening apocalyptic situation and it requires international efforts and collaboration to prevent a global crisis.

Emerging infectious diseases Southeast Asia

Microbial Tliteats to Health: Emergence, Detection and Response

Chikungunya infection An emerging disease in Malaysia

Health problems of foi~eign workers -Microbiological investigations

Avian influenza H5N1 in tigers and leopards

Health Care Response to HIV in the Third World: Challenges and Strategies Hoosen M. COOVADIA. University of Natal, Durban, South Africa Introduction: Healtficare responses to the global HIV/AIDS pandemic can o/fly be fommlated on the basis of accurate information on the size, distribution mid epidemiology of the infection. The most reliable figures on global prevalence of H1V and of AIDS are those that are issued annually from UNAIDS/Wt-IO. These numbers are mainly estimated from the regular antenatal surveys conducted in the most affected countries. Population-based samples in a few countries, including South Africa, provide additional data. Both methods have their particular shortcomings. In general, the ANC figures appear to be higher than those that are population-based: the truth probably lies anmewfiere in between, and our searches for the nearest approximation must continue. The lack of absolute precision, as demanded by some critics, is not a mason for paralysis. In South Africa, considerable public confusion and much harm is done through persistent questioning by a few well-connected individuals of the accuracy of such prevalence figmes. The gulf between the South African state and civil society on HIV/AIDS, of which these continuing doubts on the size of the epidemic are but one illustration, will be discussed. This will be done in the context of emphasizing the centrality of political and government support complete, unconditional, and enthusiastic in the efforts to confront and control tiffs epidemic.Background: The current estimates indicate that there are 38 million people living with HIV and the epidemic continues to increase, with almost every region in the world being involved. Africa remains the worst affected; India, China, Eastern Europe, and the Carribbean countries have sizable epidemics. The target groups for whom appropriate interventions for prevention and care are desperately needed are women, adolescents, young adults, and those who live in poverty. In Kwazulu/Natal, South Africa, the prevalence of HIV among young women between the ages of 20 29 years attending antenatal clinics goes up to about 50%.Discussion: Heterosexual transmission is the main route of transmis sion. It has been estimated that for every 10 000 contacts there are 80 HIV infections for receptive anal sex, 20 for receptive vaginal sex, and 3 for insertive anal/vaginal sex. These figures are to be compared to 60 HIV itffections for needle sharing and 33 for occupational needle-stick injuiy per 10000 contacts. Sexually transmitted infections have been shown repeatedly to predispose to HIV infection. Prevention programs are a key challenge; of persons worldwide who require prevention services less than 20% have access to them. Prevention of motfier-to-child-transmission