Reestablishment Of Transmission Research Articles

Health Inequalities in India – Will Looking through the Social Determinants Lens, Make a Difference?

Shrinking the global malaria map is one of the most remarkable successes of modern public health since the end of Second World War. More than 100 countries have successfully eliminated malaria since the early 20th century. Consequently, 20% additional population got the opportunity to live in malaria-free areas in the 60-years period between 1950 and 2010.1Currently, the disease is endemic in only 31 countries and India is featured in the list of top 20 malaria-endemic countries that together contributed 85% the global malaria burden.2India is also the only country outside Africa to be featured in that list.Government of India has set the target to eliminate malaria by 2030. In order to achieve the elimination certificate, the country has to be freed of malaria transmission by 2027 and the re-establishment of transmission is to be prevented in the subsequent years. With this ambitious goal set in 2016, the country has taken a tremendous stride in reducing the malaria cases over the past five years from about 1.1 million in 20143 to about 0.43 million in 20184. The percentage reduction in malaria cases during this 5-years period has been more than what India had achieved during the 15-years period since 2000. More importantly, the steep decline in malaria burden has been witnessed during a period when the global malaria response is at the crossroads with a static annual incidence of the disease since 2014.5

Progress Toward Poliovirus Containment Implementation - Worldwide, 2017-2018.

Substantial progress has been made since the World Health Assembly (WHA) resolved to eradicate poliomyelitis in 1988 (1). Among the three wild poliovirus (WPV) types, type 2 (WPV2) was declared eradicated in 2015, and type 3 (WPV3) has not been reported since 2012 (1). In 2017 and 2018, only Afghanistan and Pakistan have reported WPV type 1 (WPV1) transmission (1). When global eradication of poliomyelitis is achieved, facilities retaining poliovirus materials need to minimize the risk for reintroduction of poliovirus into communities and reestablishment of transmission. Poliovirus containment includes biorisk management requirements for laboratories, vaccine production sites, and other facilities that retain polioviruses after eradication; the initial milestones are for containment of type 2 polioviruses (PV2s). At the 71st WHA in 2018, World Health Organization (WHO) Member States adopted a resolution urging acceleration of poliovirus containment activities globally, including establishment by the end of 2018 of national authorities for containment (NACs) to oversee poliovirus containment (2). This report summarizes containment progress since the previous report (3) and outlines remaining challenges. As of August 2018, 29 countries had designated 81 facilities to retain PV2 materials; 22 of these countries had established NACs. Although there has been substantial progress, intensification of containment measures is needed.

MalERA: An updated research agenda for diagnostics, drugs, vaccines, and vector control in malaria elimination and eradication.

Since the turn of the century, a remarkable expansion has been achieved in the range and effectiveness of products and strategies available to prevent, treat, and control malaria, including advances in diagnostics, drugs, vaccines, and vector control. These advances have once again put malaria elimination on the agenda. However, it is clear that even with the means available today, malaria control and elimination pose a formidable challenge in many settings. Thus, currently available resources must be used more effectively, and new products and approaches likely to achieve these goals must be developed. This paper considers tools (both those available and others that may be required) to achieve and maintain malaria elimination. New diagnostics are needed to direct treatment and detect transmission potential; new drugs and vaccines to overcome existing resistance and protect against clinical and severe disease, as well as block transmission and prevent relapses; and new vector control measures to overcome insecticide resistance and more powerfully interrupt transmission. It is also essential that strategies for combining new and existing approaches are developed for different settings to maximise their longevity and effectiveness in areas with continuing transmission and receptivity. For areas where local elimination has been recently achieved, understanding which measures are needed to maintain elimination is necessary to prevent rebound and the reestablishment of transmission. This becomes increasingly important as more countries move towards elimination.

Control, elimination, eradication and re-emergence of infectious diseases: getting the message right

During the 25 years since the certification of smallpox eradication there has been considerable debate among public health practitioners about how existing health technologies can best be used to decrease infectious disease incidence and prevalence. Interruption of transmission has often been envisaged as the ultimate goal, and standard public health concepts of disease reduction have been defined or re-defined. In 1998, Dowdle proposed a definition of control as a reduction in the incidence, prevalence, morbidity or mortality of an infectious disease to a locally acceptable level; elimination as reduction to zero of the incidence of disease or infection in a defined geographical area; and eradication as permanent reduction to zero of the worldwide incidence of infection. (1) Whereas the proposed definition of eradication emphasizes that routine intervention measures are no longer needed once interruption of transmission has been certified worldwide, inherent in the definitions of control and elimination is the need for continued intervention measures to prevent re-emergence and re-establishment of transmission. It is this need for continued intervention after reaching control or elimination targets that has been the source of confusion among public health workers, health policy-makers and the politicians who provide resources for infectious disease control. At times, misunderstanding has led to neglect or complete cessation of intervention activities, with concurrent decrease in financial resources, and thus to re-emergence of the target disease. In this issue of the Bulletin, Song Liang et al. (pp. 139-144) describe schistosomiasis in eight counties in the Sichuan Province of China that reemerged an average of 8.1 years after attainment of control targets in seven counties and interruption of transmission in the eighth. Control and interruption of transmission had been attained through a mixture of interventions including mollusc control, chemotherapy, health education and provision of clean water. Surveillance to determine where disease was present in humans, snails and cattle underpinned control activities and continued in some form in most counties after attainment of control targets. Most other interventions to control infection in the snail vector and human host were, however, discontinued. (2) The authors underscore the role of mobility of humans and cattle in the re-introduction of schistosomiasis from adjacent counties where control targets had not yet been met, and the role that cessation of control activities played in the subsequent re-emergence of indigenous transmission. They cite decreased funding, lack of awareness, and apathy as causes for the cessation of control activities, and describe the weakness in surveillance that resulted in late detection of human infection. In today's world of rapid travel and transport, re-introduction of infectious diseases occurs not only locally: humans, insects, livestock and food products carry infectious agents from country to country and from continent to continent. …