Successes and challenges of expansion of environmental poliovirus surveillance in the WHO South-East Asia Region.

The last decade has witnessed an exponential expansion of environmental surveillance (ES) of poliovirus in sewage samples in the World Health Organization (WHO) South-East Asia Region. This has grown from only three sites in Mumbai, India in 2001 to 56 sites in 2017 in Bangladesh, India, Indonesia, Myanmar, Nepal and Thailand. ES is critical to the region in providing evidence of silent transmission of vaccine-derived poliovirus and Sabin-like poliovirus type 2 - especially since the global "switch" to cease use of oral polio vaccine type 2 - and for monitoring the effectiveness of containment activities.

Progress Toward Rubella and Congenital Rubella Syndrome Control - South-East Asia Region, 2000-2016.

In 2013, the 66th session of the Regional Committee of the World Health Organization (WHO) South-East Asia Region (SEAR)* adopted the goal of elimination of measles and control of rubella and congenital rubella syndrome (CRS) by 2020 (1). Rubella is the leading vaccine-preventable cause of birth defects. Although rubella typically causes a mild fever and rash in children and adults, rubella virus infection during pregnancy, especially during the first trimester, can result in miscarriage, fetal death, or a constellation of congenital malformations known as CRS, commonly including visual, auditory, and/or cardiac defects, and developmental delay (2).

Japanese Encephalitis Surveillance and Immunization - Asia and Western Pacific Regions, 2016.

Japanese encephalitis (JE) virus is the most important vaccine-preventable cause of encephalitis in the Asia-Pacific region. The World Health Organization (WHO) recommends integration of JE vaccination into national immunization schedules in all areas where the disease is a public health priority (1). This report updates a previous summary of JE surveillance and immunization programs in Asia and the Western Pacific in 2012 (2).

Virologic Monitoring of Poliovirus Type 2 after Oral Poliovirus Vaccine Type 2 Withdrawal in April 2016 - Worldwide, 2016-2017.

The Global Polio Eradication Initiative (GPEI) has made substantial progress since its launch in 1988; only 37 wild poliovirus type 1 (WPV1) cases were detected in 2016, the lowest annual count ever. Wild poliovirus type 3 has not been detected since November 2012, and wild poliovirus type 2 was officially declared eradicated in September 2015. This success is attributable to the wide use of live oral poliovirus vaccines (OPVs).

Global Measles and Rubella Laboratory Network Support for Elimination Goals, 2010-2015.

In 2012, the World Health Assembly endorsed the Global Vaccine Action Plan (GVAP)* with the objective to eliminate measles and rubella in five World Health Organization (WHO) regions by 2020. In September 2013, countries in all six WHO regions had established measles elimination goals, and additional goals for elimination of rubella and congenital rubella syndrome were established in three regions (1). Capacity for surveillance, including laboratory confirmation, is fundamental to monitoring and verifying elimination.

Influenza seasonality and vaccination timing in tropical and subtropical areas of southern and south-eastern Asia.

Objective: To characterize influenza seasonality and identify the best time of the year for vaccination against influenza in tropical and subtropical countries of southern and south-eastern Asia that lie north of the equator.

Methods: Weekly influenza surveillance data for 2006 to 2011 were obtained from Bangladesh, Cambodia, India, Indonesia, the Lao People's Democratic Republic, Malaysia, the Philippines, Singapore, Thailand and Viet Nam. Weekly rates of influenza activity were based on the percentage of all nasopharyngeal samples collected during the year that tested positive for influenza virus or viral nucleic acid on any given week.

Prospective study of avian influenza virus infections among rural Thai villagers.

Background: In 2008, 800 rural Thai adults living within Kamphaeng Phet Province were enrolled in a prospective cohort study of zoonotic influenza transmission. Serological analyses of enrollment sera suggested this cohort had experienced subclinical avian influenza virus (AIV) infections with H9N2 and H5N1 viruses.

Methods: After enrollment, participants were contacted weekly for 24 mos for acute influenza-like illnesses (ILI).

Vaccine-related mumps infections in Thailand and the identification of a novel mutation in the mumps fusion protein.

An outbreak of nine cases of mumps was reported from a total of 97 vaccinated nursing students at two medical colleges in Thailand in 2010, 16-26 days after administration of MMR vaccine containing the L-Zagreb mumps strain. Symptoms ranged in severity from fever and parotid swelling to orchitis. Clinical samples were obtained from seven patients and three were suitable for further study.

Genetic characterization of measles viruses that circulated in Thailand from 1998 to 2008.

During the period between 1998 and 2008, 48 representative measles viruses (MeVs) circulating in Thailand were subjected to genetic characterization. Three genotypes, G2, D5, and D9 were detected. The results suggested that measles genotype D5, which has been circulating since at least 1998, is the endemic genotype in Thailand.

Evidence for subclinical avian influenza virus infections among rural Thai villagers.

Background: Regions of Thailand reported sporadic outbreaks of A/H5N1 highly pathogenic avian influenza (HPAI) among poultry between 2004 and 2008. Kamphaeng Phet Province, in north-central Thailand had over 50 HPAI poultry outbreaks in 2004 alone, and 1 confirmed and 2 likely other human HPAI infections between 2004 and 2006.

Methods: In 2008, we enrolled a cohort of 800 rural Thai adults living in 8 sites within Kamphaeng Phet Province in a prospective study of zoonotic influenza transmission.

Status of global virologic surveillance for rubella viruses.

The suspected measles case definition captures rubella cases. Therefore, measles surveillance will be improved in the course of the control and eventual elimination of rubella transmission. One aspect of rubella control, virologic surveillance, is reviewed here.

Global distribution of measles genotypes and measles molecular epidemiology.

A critical component of laboratory surveillance for measles is the genetic characterization of circulating wild-type viruses. The World Health Organization (WHO) Measles and Rubella Laboratory Network (LabNet), provides for standardized testing in 183 countries and supports genetic characterization of currently circulating strains of measles viruses. The goal of this report is to describe the lessons learned from nearly 20 years of virologic surveillance for measles, to describe the global databases for measles sequences, and to provide regional updates about measles genotypes detected by recent surveillance activities.

Developing rubella vaccination policy in Nepal--results from rubella surveillance and seroprevalence and congenital rubella syndrome studies.

Background: The Government of Nepal is interested in preventing congenital rubella syndrome (CRS). Surveillance data were analyzed and studies conducted to assess the burden of rubella and CRS and aid in developing a rubella vaccination strategy.

Methods: (1) Analysis of rubella cases reported through measles surveillance, 2004-2009; (2) in 2008, rubella seroprevalence among women 15 to 39 years of age was evaluated; and (3) in 2009, children attending a school for the deaf were examined for ocular defects associated with CRS.

A comparison study of measles antibody between two doses vaccination at 9, 18 months and single dose at 9 months in children 4-6 years old.

Background: The authors have added the second dose of measles vaccine to children aged 18 months since 1997 because of the measles outbreaks in Nan province in 1993-1994.

Objective: To compare measles antibody level between two doses vaccination at 9, 18 months and single dose at 9 months in children at the age of 4 to 6 years old.

Material And Method: A cross sectional serological study in children 4 to 6 years old was performed between August 2008 and August 2009 at three hospitals in Nan and Phrae provinces.

Antibody response to an eight-site intradermal rabies vaccination in patients infected with Human Immunodeficiency Virus.

Objective: To investigate the rabies virus neutralizing antibody response in HIV-1-infected patients with CD4+ cell count 200 cells/microL after post-exposure prophylaxis using an eight-site intradermal rabies vaccination regimen.

Methods: In a prospective cohort study, 27 HIV-1 infected patients were recruited, none of which had a history of rabies vaccination. All patients provided informed consent and were separated into two groups according to their CD4+ cell count (patients with CD4+ counts of 200 cells/microL).

Measles antibody in mothers and infants 0-2 years and response to measles vaccine at the age of 9 and 18 months.

Background: Despite the declining trends in measles cases corresponding to an increase in routine measles immunization coverage, measles outbreaks occur in some isolated areas in Nan province, northern Thailand. The primary reason for these outbreaks is inadequate vaccine coverage. Another reason is primary vaccine failure.

Development of serological assays for Thottapalayam virus, an insectivore-borne Hantavirus.

Thottapalayam virus (TPMV), a member of the genus Hantavirus in the family Bunyaviridae, was isolated from an insectivore, Suncus murinus (musk shrew), captured in southern India in 1964. While the isolation of TPMV predates the discovery of the prototype Hantaan virus, little is known about its genetics and biology. To date, preliminary evidence suggests that TPMV differs significantly, both antigenically and genetically, from all known rodent-borne hantaviruses.

Geographical distribution of hantaviruses in Thailand and potential human health significance of Thailand virus.

Phylogenetic investigations, sequence comparisons, and antigenic cross-reactivity studies confirmed the classification of Thailand virus (THAIV) as a distinct hantavirus species. The examination of sera from 402 rodents trapped in 19 provinces of Thailand revealed that five greater bandicoot rats (Bandicota indica) and one lesser bandicoot rat (B. savilei) from four provinces were focus reduction neutralization test (FRNT) antibody-positive for THAIV.

Antibody response after measles immunization.

Rationale: Measles is still an important public health problem in Thailand despite measles vaccination being practiced since 1984. Vaccine failure is one of the suspected reasons for the high incidence of measles.

Objective: To study the seroconversion rate of 9-month-old infants and to study the antibody level in 18 month-old and 4 year-old children who had measles vaccination at 9 months of age.