Concurrent outbreaks of circulating vaccine-derived poliovirus types 1 and 2 affecting the Republic of the Philippines and Malaysia, 2019-2021.

Concurrent outbreaks of circulating vaccine-derived poliovirus serotypes 1 and 2 (cVDPV1, cVDPV2) were confirmed in the Republic of the Philippines in September 2019 and were subsequently confirmed in Malaysia by early 2020. There is continuous population subgroup movement in specific geographies between the two countries. Outbreak response efforts focused on sequential supplemental immunization activities with monovalent Sabin strain oral poliovirus vaccine type 2 (mOPV2) and bivalent oral poliovirus vaccines (bOPV, containing Sabin strain types 1 and 3) as well as activities to enhance poliovirus surveillance sensitivity to detect virus circulation. A total of six cVDPV1 cases, 13 cVDPV2 cases, and one immunodeficiency-associated vaccine-derived poliovirus type 2 case were detected, and there were 35 cVDPV1 and 31 cVDPV2 isolates from environmental surveillance sewage collection sites. No further cVDPV1 or cVDPV2 have been detected in either country since March 2020. Response efforts in both countries encountered challenges, particularly those caused by the global COVID-19 pandemic. Important lessons were identified and could be useful for other countries that experience outbreaks of concurrent cVDPV serotypes.

The Lao Experience in Deploying Influenza A(H1N1)pdm09 Vaccine: Lessons Made Relevant in Preparing for Present Day Pandemic Threats.

The Lao PDR, as did most countries of the Mekong Region, embarked on a pandemic vaccine initiative to counter the threat posed by influenza A(H1N1)pdm09. Overall, estimated vaccine coverage of the Lao population was 14%, with uptake in targeted health care workers and pregnant women 99% and 41%, respectively. Adverse Events Following Immunization accounted for only 6% of survey driven, reported vaccination experiences, with no severe consequences or deaths. Public acceptability of the vaccine campaign was high (98%). Challenges to vaccine deployment included: 1) no previous experience in fielding a seasonal influenza vaccine, 2) safety and efficacy concerns, and 3) late arrival of vaccine 10 months into the pandemic. The Lao success in surmounting these hurdles was in large measure attributed to the oversight assigned the National Immunization Program, and national sensitivities in responding to the avian influenza A(H5N1) crisis in the years leading up to the pandemic. The Lao "lessons learned" from pandemic vaccine deployment are made even more relevant four years on, given the many avian influenza strains circulating in the region, all with pandemic potential.

Seasonal influenza vaccine policies, recommendations and use in the World Health Organization's Western Pacific Region.

OBJECTIVE: Vaccination is the most effective way to prevent seasonal influenza and its severe outcomes. The objective of our study was to synthesize information on seasonal influenza vaccination policies, recommendations and practices in place in 2011 for all countries and areas in the Western Pacific Region of the World Health Organization (WHO). METHODS: Data were collected via a questionnaire on seasonal influenza vaccination policies, recommendations and practices in place in 2011. RESULTS: Thirty-six of the 37 countries and areas (97%) responded to the survey. Eighteen (50%) reported having established seasonal influenza vaccination policies, an additional seven (19%) reported having recommendations for risk groups for seasonal influenza vaccination only and 11 (30%) reported having no policies or recommendations in place. Of the 25 countries and areas with policies or recommendations, health-care workers and the elderly were most frequently recommended for vaccination; 24 (96%) countries and areas recommended vaccinating these groups, followed by pregnant women (19 [76%]), people with chronic illness (18 [72%]) and children (15 [60%]). Twenty-six (72%) countries and areas reported having seasonal influenza vaccines available through public funding, private market purchase or both. Most of these countries and areas purchased only enough vaccine to cover 25% or less of their populations. DISCUSSION: In light of the new WHO position paper on influenza vaccines published in 2012 and the increasing availability of country-specific data, countries and areas should consider reviewing or developing their seasonal influenza vaccination policies to reduce morbidity and mortality associated with annual epidemics and as part of ongoing efforts for pandemic preparedness.

Integration of deworming into an existing immunisation and vitamin A supplementation campaign is a highly effective approach to maximise health benefits with minimal cost in Lao PDR.

Infection with soil-transmitted helminths (STH) is a major public health problem in many developing countries, with pregnant women and children particularly at risk. Preventive chemotherapy, which is the intervention currently recommended by the WHO against the main helminth infections including those caused by STHs, aims at reducing morbidity through periodical administration of anthelminthic drugs either alone or in combination. The Expanded Programme on Immunization is one of the most widely implemented health programmes in the world and has well established access to children and women. The present study investigated the cost of the provision of anthelminthic drugs during existing immunisation campaigns. In Lao PDR, use of this integrated approach compared with implementation of the vertical deworming campaign alone allowed a reduction of the individual cost of deworming by 10 times (from US$0.23 in the vertical deworming campaign to US$0.03 in the integrated campaign). When drug cost was excluded, the cost of deworming an individual was US$0.007, implying that deworming 100 children would cost less than US$1 if drug donation was in place. The burden posed on health workers by the integration process was perceived as minimal and manageable. Moreover, delivery of anthelminthic drugs during immunisation campaigns enabled campaign teams to observe drug intake directly, which assured safety. These findings prove that integration is an opportunity to maximise health benefits through the delivery of multiple health products and the attainment of high coverage.

Genetic characterization of wild-type measles viruses in Cambodia.

Cambodian authorities in collaboration with the World Health Organization (WHO) are implementing a measles control plan in this measles endemic country. Genetic characterization of Cambodian wild-type measles viruses was performed to determine the genotypes involved in outbreaks, and to measure the level of virus circulation in a geographic area just beginning to implement the measles control program. Seventy-two sequences of the C terminus of the nucleoprotein gene of measles virus were obtained from 88 patients. Samples were taken from 35 among 519 outbreaks reported to the Cambodian National Immunization Program between March 2001 and June 2002. The sequences were grouped into 10 lineages which all belonged to genotype D5. The maximum nucleotide divergence was 1.3%.