Emergence of an exotic strain of serotype O foot-and-mouth disease virus O/ME-SA/Ind-2001d in South-East Asia in 2015.

The O/Middle East-South Asia (ME-SA)/Ind-2001 lineage of foot-and-mouth disease virus (FMDV) is endemic in the Indian subcontinent and has been reported in the Middle East and North Africa, but it had not been detected in South-East Asia (SEA) before 2015. This study reports the recent incursions of this viral lineage into SEA, which caused outbreaks in Vientiane Capital of Lao People's Democratic Republic (PDR) in April 2015, in Dak Nong, Dak Lak and Ninh Thuan Provinces of Vietnam from May to October 2015, and in Rakhine State of Myanmar in October 2015. Disease investigations were conducted during the outbreaks and followed up after laboratory results confirmed the involvement of FMDV O/ME-SA/Ind-2001 sublineage d (O/ME-SA/Ind-2001d). Affected host species included cattle, buffalo and pig, and all the outbreaks resolved within 2 months. Animals with clinical signs were separated, and affected premises were disinfected. However, strict movement restrictions were not enforced, and emergency vaccinations were only implemented in Vientiane Capital of Lao PDR and Dak Nong and Ninh Thuan Provinces of Vietnam. Clinical samples were collected from each outbreak and examined by nucleotide sequencing of the FMDV viral protein 1 coding region. Sequence analysis revealed that the O/ME-SA/Ind-2001d isolates from Lao PDR and Vietnam were closely related to each other and similar to viruses previously circulating in India in 2013. Viruses collected from Myanmar were divergent from viruses of the same sublineage recovered from Lao PDR and Vietnam but were closely related to viruses present in Bangladesh in 2015. These findings imply that at least two independent introductions of O/ME-SA/Ind-2001d into SEA have occurred. Our study highlights the transboundary nature of foot-and-mouth disease (FMD) and reinforces the importance of improved FMD surveillance and promotion of safer cross-border trade in SEA to control the risk of introduction and spread of exotic FMDV strains.

Foot-and-mouth disease control and eradication in the Bicol Surveillance Buffer Zone of the Philippines.

Following the onset of an epidemic of foot and mouth disease (FMD) commencing in 1994 and affecting mainly pigs in the Philippines, a National Plan for the Control and Eradication of the disease was initiated. A disease surveillance buffer zone in the southern Luzon region of Bicol was established to protect the Visayas and Mindanao from infection and enable eventual elimination of the disease in Luzon. With achievement of Office International Epizooties (OIE)-certified FMD freedom with vaccination in the Philippines now imminent, the four components of the disease control strategy are reviewed, including quarantine and animal movement controls, strategic vaccination, surveillance and disease investigation, and enhanced public awareness with school on the air radio programmes. Although numbers of outbreaks declined following widespread vaccination, evaluation of serological responses in vaccinates suggested low levels of immune protection. The cessation of outbreaks was considered more likely a result of animal movement controls, improved surveillance and emergency response capability, and reduction in FMD-risk behaviours by livestock owners, particularly through efforts to enhance public awareness of biosecurity measures by the training of traders, livestock industry personnel and both commercial and smallholder farmers. A two-stage random sampling serosurveillance strategy enabled identification of residual infection that was not detected through opportunistic sampling and negative incident reporting. Intensive investigations of FMD outbreaks, particularly in Albay province in 1999, enabled improved understanding of the risk factors involved in disease transmission and implementation of appropriate interventions. The findings from this review are offered to assist development of FMD control and eradication programmes in other countries in south-east Asia that are now being encouraged to support the OIE goal of FMD freedom with vaccination by 2020.