Streptococcus agalactiae in the environment of bovine dairy herds – rewriting the textbooks?

Streptococcus agalactiae Serotype IV in Humans and Cattle, Northern Europe1

“…ST19 is generally rare in cattle, although its association with humans is not absolute ( 11 , 12 ). Conversely, ST103 was commonly found in cattle in our study and in Denmark, Norway, and China ( 12 , 26 , 40 ) but not in isolates from humans in our study or those mentioned in any of the references cited. ST103 and its SLVs were invariably associated with serotype Ia ( 40 ) and PI-2b (Technical Appendix Figure 5).…”

“…In one prospective study, increased frequency of cattle exposure was associated with human colonization with S. agalactiae , although fecal colonization was detected in 1 cow only ( 14 ). The prevalence of fecal colonization on individual farms can be high ( 26 ), but gastrointestinal carriage is much more widespread among humans ( 16 , 29 ), which argues against exposure to cattle feces as a dominant reservoir for human colonization. Case reports and phenotyping of isolates show that raw milk consumption may lead to colonization of the human throat ( 30 ).…”

“…Potentially shared sources include wastewater and surface water, including effluent from sewage treatment plants ( 27 , 35 , 36 ). Potential routes of within- and between-host species transmission, including horizontal and vertical transmission among humans ( 12 , 31 , 37 ) and contagious transmission among cattle via milking machines ( 12 , 26 ), are summarized in Technical Appendix Figure 6.…”

An update on environmental mastitis: Challenging perceptions

“…Molecular epidemiology studies have been important in elucidating the range of transmission modes within mastitis‐causing pathogen species, and it is increasingly clear that the distinction between contagious and environmental pathogens should be applied at strain level rather than species level (Gurjar et al., ; Zadoks et al., ). Streptococcus agalactiae , long considered the quintessential contagious pathogen, may originate from humans (Dogan et al., ) or faeces (Farre et al., ; Jørgensen et al., ). Klebsiella pneumoniae , almost exclusively seen as environmental pathogen, may occasionally spread from cow to cow (Munoz et al., ; Schukken et al., ).…”

Indirect enzyme-linked immunosorbent assay method based on Streptococcus agalactiae rSip-Pgk-FbsA fusion protein for detection of bovine mastitis

“…Currently, the commonly used laboratory serological detection methods include an enzyme-linked immunosorbent assay (ELISA), agar diffusion test, or agglutination test (Meiri-Bendek et al 2002, Vidovh et al 2009, Jzrgensen et al 2016. Among these tests, ELISA has certain advantages such as simplicity, convenience for batch testing, high throughput, high sensitivity, strong specificity, and cost-effectiveness.…”