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A non‐haemadsorbing (non‐HAD) ASF virus (ASFV) genotype II, namely Lv17/WB/Rie1, was isolated from a hunted wild boar in Latvia in 2017. Domestic pigs experimentally infected with the non‐HAD ASFV developed a nonspecific or subclinical form of the disease. Two months later, these animals were fully protected when exposed to other domestic pigs infected with a related virulent HAD genotype II ASFV.

The purpose of this study was to describe prevalence and spatial distribution of Coxiella burnetii infections in dairy cow sheds in Latvia and to investigate risk factors contributing to C. burnetii infections. Blood serum samples from abortion cases from 1010 sheds have been tested by ELISA for the presence of C. burnetii antibodies and bulk tank milk (BTM) samples from 252 sheds have been tested by real time polymerase chain reaction and ELISA for the presence of C. burnetii DNA and antibodies. Prevalence of C. burnetii antibody-positive sheds in cases of abortion was 13·4%. A total of 10·7% and 13·2% of dairy cow sheds tested positive for the presence of C. burnetii DNA and antibodies in BTM, respectively. Two distinct areas of clustering of test-positive dairy cattle sheds were identified by spatial scan statistics of abortion cases and randomly sampled BTM samples. Three factors were identified as significantly contributing to the risk of C. burnetii DNA presence in BTM - number of cattle in shed (>200 animals/shed) (OR 3·93), location of the shed within risk area in Northern Latvia (OR 8·29) and for the first time, purchasing cattle from abroad has been shown to significantly increase risk (OR 2·68) of C. burnetii infection in dairy cows in Latvia.

Brucellosis due to Brucella suis biovar 2 is one of the most important endemic diseases in wild boar (Sus scrofa) populations in Europe. The aim of the present study was to determine the seroprevalence of brucellosis in wild boars in the eastern part of Latvia. Wild boars killed by hunters in the period from January to April 2015 (n = 877) and from March to April in 2016 (n = 167) were examined for antibodies against B. suis by the Rose Bengal test (RBT), a complement fixation test (CFT), and by enzyme-linked immunosorbent assays. In 2015, 199 samples (22.7%) were positive by RBT and/or CFT while 36 samples (21.6%) were seropositive in 2016. Of the Brucella seropositive samples from 2015 and 2016 (n = 235), 162 (68.9%) were also seropositive to Yersinia enterocolitica. Considering cross-reactivity of serological tests, the seroprevalence of B. suis biovar 2 exposure in wild boars in the eastern part of Latvia was calculated to 14.0% in 2015 and 9.6% in 2016. From selected seropositive samples (42 in 2015 and 36 in 2016) total DNA was extracted and analyzed with an IS711-based nested polymerase chain reaction (PCR) assay. Species and biovar identification was conducted for bacteria isolated in monoculture from PCR positive samples by species specific primers and Bruce-ladder multiplex PCR. Brucella suis biovar 2 was isolated from 12/20 samples in 2015 and 9/9 samples in 2016. The average seroprevalence was relatively low compared to that found in certain other European countries. Males and females had an equal level of seropositivity, but a positive age-trend was observed for both males and females.

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