Investigation on the Prevalence of Canine Microfilaremia in Thailand Using a Novel Microfluidic Device in Combination with Real-Time PCR

We conducted a survey of canine microfilaraemia in 768 dogs in Chanthaburi, Samut Sakhon, and Narathiwat provinces of Thailand using a novel semi-automated, microfluidic device that is easy and rapid to perform. Microfilariae species were identified using High Resolution Melting real-time PCR (HRM real-time PCR). The prevalence of canine microfilaremia was 16.2% (45/278) in Chanthaburi and 5.5% (12/217) in Samut Sakhon. The prevalence of canine microfilaremia in Narathiwat was 22.7% (67/273). Brugia pahangi and Dirofilaria immitis were the predominant species of filariae found in the infected dogs from Chanthaburi and Narathiwat, respectively. The low prevalence of canine microfilaremia of Samut Sakhon may reflect the success of the Soi Dog foundation's efforts and the establishment of veterinary control programs. An effective disease control and prevention strategies is needed in Chanthaburi and Narathiwat to reduce the risks of zoonotic transmission of the parasites. An appropriate drug treatment should be given to infected dogs and prophylactic drugs are suggested to be given to dogs age <= 1-year-old to prevent filarial infection. The novel microfluidic device could be implemented for surveillance of filariae infection in other animals.

Automated summary

The study found varying prevalence of canine microfilaremia in three provinces of Thailand, with Brugia pahangi and Dirofilaria immitis being the predominant species. The lower prevalence in Samut Sakhon could be attributed to the successful efforts of the Soi Dog foundation. Effective disease control and prevention strategies are needed in Chanthaburi and Narathiwat to reduce the risks of zoonotic transmission.