Costa Rica gained its Newcastle Disease Virus NDV-free status with vaccination according to OIE proceedings in 1996, and its declaration as a country free of the velogenic, viscerotropic form of this disease (G/SPS/GEN/119) presented to the World Trade Organization (WTO) in 1999. On April 24th, 2015, SENASA (National Animal Health Service) attended a velogenic Newcastle disease outbreak that affected backyard chickens in a small town (Bellavista, Guanacaste) in the northern part of the country, near the Nicaraguan border. Sixty-five backyard birds died from a total of 84 exposed animals. Blood samples, cloacal swabs, tracheal swabs, cecal tonsils, lung and trachea tissues were collected for diagnosis at the National Veterinary Services Laboratory (LANASEVE). These samples were screened for Avian Influenza (AIV) and NDV. All samples were negative for Avian Influenza in ELISA test and RT-PCR. Serum samples were positive for NDV antibody by hemagglutination inhibition test, and tissue and swab samples were positive for NDV by conventional RT-qPCR targeting a 310 bp fragment of the virus fusion protein gene. The amino acid sequence of the protease cleavage site within the amplicon matched the sequence of a virulent strain (112RRQKRF117). The nucleotide sequence had a 98.7% identity and an e value of 4e-153 with a genotype V velogenic sequence from Belize (KF767467) and Honduras (JN872194) collected in 2008 and 2007, respectively, according to BLASTN. A total of 3604 backyard birds were euthanized in town and its surroundings (1 km), including 3495 chickens, 66 turkeys, 6 geese, and 37 ducks. The case was considered resolved, and OIE was notified in November 2015 following OIE guidelines. In April 2017, Costa Rica recovered its disease-free status through executive decree No. 40301-MAG.

Classical swine fever (CSF) is a highly contagious viral disease that affects pigs and wild boars. The disease can cause significant economic losses in the pig industry and poses a threat to food security. Therefore, it is crucial to have effective surveillance programs to detect and control the disease. The study mentioned above aimed to compare three commercial ELISA kits for the detection of CSF antibodies. The results showed that all three kits had 100% congruence in undiluted samples, indicating that they are highly reliable for use as a screening test on routine samples. Additionally, the study found good reproducibility between technicians with no significant influence on the variation of results. However, the study also identified a low consistency of positive results (37.7%) for the kit IDvet Screen E2 in diluted samples, with significant variations in results from all three kits. This finding suggests that the other two kits, Herdchek E2 and Priocheck E2, may be better suited for detecting animals with low levels of antibodies, allowing for earlier detection of infected animals and the implementation of relevant control measures. In conclusion, the study demonstrates the importance of using high-quality commercial ELISA kits for the surveillance of CSF. The findings suggest that any of the three kits tested could be used as a reliable screening test on routine samples. However, for the detection of animals with low levels of antibodies, the Herdchek E2 and Priocheck E2 kits may be more effective