Human exposure to Brucella abortus S19 strain: serological, clinical and epidemiological findings

JORGE WALLACH; M. VICTORIA DELPINO; MARIANA FERRERO; CARLOS A. FOSSATI; PABLO C. BALDI

Mexico

Congreso; 58 th Brucellosis 2005. International Research Conference; 2005

Abstract In Argentina brucellosis is mainly an occupational disease, specially among meat industry personnel and rural workers. During cattle vaccination with Brucella abortus S19 strain, some individuals suffer accidental exposures that can lead to clinically and serologically active brucellosis. We studied 53 individuals potentially exposed to B. abortus S19 strain, including 25 employees from laboratories producing the vaccine and 28 individuals (13 veterinarians and 15 technicians) involved in cattle vaccination (rural workers). Patients were recruited by active screening or consulted spontaneously. Among laboratory employees, 5 recalled specific accidental exposures (1 splash, 4 skin cuts) and 21 did not. Among rural workers, 13 recalled needle sticks during vaccination and 2 recalled facial splashes. The remaining 13 rural workers reported frequent hand contact with the vaccine suspension, but they did not consider this as an accidental exposure. From all the studied individuals, 31 (58%) had clinical manifestations at recruitment. Symptoms included: fever (17), asthenia (15), myalgia (9), arthralgia (13), sweats (9), headache (12), weight loss (5), irritability (4), depression (4). Differential blood counts (performed in 28 cases) revealed  lymphocytosis in 11 cases. Blood cultures were performed in 12 cases, all with negative results. Classical serological tests (STA, 2ME, Rose Bengal test, complement fixation) were performed in all the individuals. In addition, ELISA tests for IgG and IgM to LPS and IgG to cytosolic proteins from Brucella could be performed in 22 patients. Altogether (classical serology + ELISA), active infection was serologically diagnosed in 28 cases (60% of laboratory employees, 46% of rural workers). These results confirm that, despite its reduced virulence, the S19 strain can produce active or inactive human infection. In addition, these findings suggest that laboratory employees did not adhere to biosafety measures or that such measures should be reinforced. The high frequency of accidental infection among rural workers indicates the necessity to improve personnel training for vaccination procedures. Abstract In Argentina brucellosis is mainly an occupational disease, specially among meat industry personnel and rural workers. During cattle vaccination with Brucella abortus S19 strain, some individuals suffer accidental exposures that can lead to clinically and serologically active brucellosis. We studied 53 individuals potentially exposed to B. abortus S19 strain, including 25 employees from laboratories producing the vaccine and 28 individuals (13 veterinarians and 15 technicians) involved in cattle vaccination (rural workers). Patients were recruited by active screening or consulted spontaneously. Among laboratory employees, 5 recalled specific accidental exposures (1 splash, 4 skin cuts) and 21 did not. Among rural workers, 13 recalled needle sticks during vaccination and 2 recalled facial splashes. The remaining 13 rural workers reported frequent hand contact with the vaccine suspension, but they did not consider this as an accidental exposure. From all the studied individuals, 31 (58%) had clinical manifestations at recruitment. Symptoms included: fever (17), asthenia (15), myalgia (9), arthralgia (13), sweats (9), headache (12), weight loss (5), irritability (4), depression (4). Differential blood counts (performed in 28 cases) revealed  lymphocytosis in 11 cases. Blood cultures were performed in 12 cases, all with negative results. Classical serological tests (STA, 2ME, Rose Bengal test, complement fixation) were performed in all the individuals. In addition, ELISA tests for IgG and IgM to LPS and IgG to cytosolic proteins from Brucella could be performed in 22 patients. Altogether (classical serology + ELISA), active infection was serologically diagnosed in 28 cases (60% of laboratory employees, 46% of rural workers). These results confirm that, despite its reduced virulence, the S19 strain can produce active or inactive human infection. In addition, these findings suggest that laboratory employees did not adhere to biosafety measures or that such measures should be reinforced. The high frequency of accidental infection among rural workers indicates the necessity to improve personnel training for vaccination procedures. Abstract In Argentina brucellosis is mainly an occupational disease, specially among meat industry personnel and rural workers. During cattle vaccination with Brucella abortus S19 strain, some individuals suffer accidental exposures that can lead to clinically and serologically active brucellosis. We studied 53 individuals potentially exposed to B. abortus S19 strain, including 25 employees from laboratories producing the vaccine and 28 individuals (13 veterinarians and 15 technicians) involved in cattle vaccination (rural workers). Patients were recruited by active screening or consulted spontaneously. Among laboratory employees, 5 recalled specific accidental exposures (1 splash, 4 skin cuts) and 21 did not. Among rural workers, 13 recalled needle sticks during vaccination and 2 recalled facial splashes. The remaining 13 rural workers reported frequent hand contact with the vaccine suspension, but they did not consider this as an accidental exposure. From all the studied individuals, 31 (58%) had clinical manifestations at recruitment. Symptoms included: fever (17), asthenia (15), myalgia (9), arthralgia (13), sweats (9), headache (12), weight loss (5), irritability (4), depression (4). Differential blood counts (performed in 28 cases) revealed  lymphocytosis in 11 cases. Blood cultures were performed in 12 cases, all with negative results. Classical serological tests (STA, 2ME, Rose Bengal test, complement fixation) were performed in all the individuals. In addition, ELISA tests for IgG and IgM to LPS and IgG to cytosolic proteins from Brucella could be performed in 22 patients. Altogether (classical serology + ELISA), active infection was serologically diagnosed in 28 cases (60% of laboratory employees, 46% of rural workers). These results confirm that, despite its reduced virulence, the S19 strain can produce active or inactive human infection. In addition, these findings suggest that laboratory employees did not adhere to biosafety measures or that such measures should be reinforced. The high frequency of accidental infection among rural workers indicates the necessity to improve personnel training for vaccination procedures. Abstract In Argentina brucellosis is mainly an occupational disease, specially among meat industry personnel and rural workers. During cattle vaccination with Brucella abortus S19 strain, some individuals suffer accidental exposures that can lead to clinically and serologically active brucellosis. We studied 53 individuals potentially exposed to B. abortus S19 strain, including 25 employees from laboratories producing the vaccine and 28 individuals (13 veterinarians and 15 technicians) involved in cattle vaccination (rural workers). Patients were recruited by active screening or consulted spontaneously. Among laboratory employees, 5 recalled specific accidental exposures (1 splash, 4 skin cuts) and 21 did not. Among rural workers, 13 recalled needle sticks during vaccination and 2 recalled facial splashes. The remaining 13 rural workers reported frequent hand contact with the vaccine suspension, but they did not consider this as an accidental exposure. From all the studied individuals, 31 (58%) had clinical manifestations at recruitment. Symptoms included: fever (17), asthenia (15), myalgia (9), arthralgia (13), sweats (9), headache (12), weight loss (5), irritability (4), depression (4). Differential blood counts (performed in 28 cases) revealed  lymphocytosis in 11 cases. Blood cultures were performed in 12 cases, all with negative results. Classical serological tests (STA, 2ME, Rose Bengal test, complement fixation) were performed in all the individuals. In addition, ELISA tests for IgG and IgM to LPS and IgG to cytosolic proteins from Brucella could be performed in 22 patients. Altogether (classical serology + ELISA), active infection was serologically diagnosed in 28 cases (60% of laboratory employees, 46% of rural workers). These results confirm that, despite its reduced virulence, the S19 strain can produce active or inactive human infection. In addition, these findings suggest that laboratory employees did not adhere to biosafety measures or that such measures should be reinforced. The high frequency of accidental infection among rural workers indicates the necessity to improve personnel training for vaccination procedures. Abstract In Argentina brucellosis is mainly an occupational disease, specially among meat industry personnel and rural workers. During cattle vaccination with Brucella abortus S19 strain, some individuals suffer accidental exposures that can lead to clinically and serologically active brucellosis. We studied 53 individuals potentially exposed to B. abortus S19 strain, including 25 employees from laboratories producing the vaccine and 28 individuals (13 veterinarians and 15 technicians) involved in cattle vaccination (rural workers). Patients were recruited by active screening or consulted spontaneously. Among laboratory employees, 5 recalled specific accidental exposures (1 splash, 4 skin cuts) and 21 did not. Among rural workers, 13 recalled needle sticks during vaccination and 2 recalled facial splashes. The remaining 13 rural workers reported frequent hand contact with the vaccine suspension, but they did not consider this as an accidental exposure. From all the studied individuals, 31 (58%) had clinical manifestations at recruitment. Symptoms included: fever (17), asthenia (15), myalgia (9), arthralgia (13), sweats (9), headache (12), weight loss (5), irritability (4), depression (4). Differential blood counts (performed in 28 cases) revealed  lymphocytosis in 11 cases. Blood cultures were performed in 12 cases, all with negative results. Classical serological tests (STA, 2ME, Rose Bengal test, complement fixation) were performed in all the individuals. In addition, ELISA tests for IgG and IgM to LPS and IgG to cytosolic proteins from Brucella could be performed in 22 patients. Altogether (classical serology + ELISA), active infection was serologically diagnosed in 28 cases (60% of laboratory employees, 46% of rural workers). These results confirm that, despite its reduced virulence, the S19 strain can produce active or inactive human infection. In addition, these findings suggest that laboratory employees did not adhere to biosafety measures or that such measures should be reinforced. The high frequency of accidental infection among rural workers indicates the necessity to improve personnel training for vaccination procedures.