Evaluation of Neisseria meningitidis Carriage with the Analysis of Serogroups, Genogroups and Clonal Complexes among Polish Soldiers.

Neisseria meningitidis is an etiological factor of invasive meningococcal disease (IMD). This Gram-negative diplococcus is transmitted from person to person via droplets or through a direct physical contact with secretions of infected patients or asymptomatic carriers. The latter account for 5-10% of the general population. The aim of the study was to estimate the actual N. meningitidis carriage rate in the military environment with identification of serogroups, genogroups, sequence types and clonal complexes of the isolates detected among Polish soldiers. The study was conducted during winter seasons of 2015 and 2016 and involved 883 professional soldiers from the Armoured Brigade in Swietoszów, Poland. The material for testing were nasopharyngeal swabs obtained from study participants. The samples were tested using standard microbiological methods (culture, incubation, microscopy, biochemical and automated identification). N. meningitidis isolates were subjected to slide agglutination test (identification of serogroups), the bacterial DNA was extracted and allowed to determine genogroups, clonal complexes and sequence types. 76 soldiers were found to be carriers of N. meningitidis , they accounted for 8.6% of the study group. The meningococcal isolates mostly belonged to serogroup B. Sequence types ST-11439, ST-136, ST-1136 and the clonal complex 41/44CC were found to be predominant. Clonal complexes responsible for IMD were detected in 15.8% of carriers and 1.4% of the whole study participants. Carriage rates of N. meningitidis among Polish soldiers were found to be similar to those reported in the general population.Neisseria meningitidis is an etiological factor of invasive meningococcal disease (IMD). This Gram-negative diplococcus is transmitted from person to person via droplets or through a direct physical contact with secretions of infected patients or asymptomatic carriers. The latter account for 5­10% of the general population. The aim of the study was to estimate the actual N. meningitidis carriage rate in the military environment with identification of serogroups, genogroups, sequence types and clonal complexes of the isolates detected among Polish soldiers. The study was conducted during winter seasons of 2015 and 2016 and involved 883 professional soldiers from the Armoured Brigade in Swietoszów, Poland. The material for testing were nasopharyngeal swabs obtained from study participants. The samples were tested using standard microbiological methods (culture, incubation, microscopy, biochemical and automated identification). N. meningitidis isolates were subjected to slide agglutination test (identification of serogroups), the bacterial DNA was extracted and allowed to determine genogroups, clonal complexes and sequence types. 76 soldiers were found to be carriers of N. meningitidis, they accounted for 8.6% of the study group. The meningococcal isolates mostly belonged to serogroup B. Sequence types ST-11439, ST-136, ST-1136 and the clonal complex 41/44CC were found to be predominant. Clonal complexes responsible for IMD were detected in 15.8% of carriers and 1.4% of the whole study participants. Carriage rates of N. meningitidis among Polish soldiers were found to be similar to those reported in the general population.

Hepatitis E virus seroprevalence in Polish soldiers serving in harsh environmental conditions.

BACKGROUND: Hepatitis E virus (HEV) is an under-recognised aetiological factor of viral hepatitis; it is most commonly transmitted via the oral-faecal route, but can also be transmitted by blood or blood products, vertically from an infected mother to the foetus or by transplanted organs. The aim of the study was to present the current seroprevalence of HEV among soldiers from the Polish Special Forces deployed on military operations carried out in harsh environmental conditions. MATERIALS AND METHODS: The research conducted between October and November 2016 involved 253 active duty soldiers, 237 men and 16 women, aged 26-57, without clinical symptoms of infection, participants in military operations in Asia and Africa. Accurate HEV diagnosis required the implementation of a two-phase diagnostic protocol. During the first phase, immunoenzymatic ELISA method was used to detect specific anti-HEV antibodies (IgM and IgG) in blood serum samples indicating contact with an infectious agent in the past. During the second phase, serum samples obtained from subjects with positive or inconclusive test results were tested again using confirmatory recomLine HEV IgM/IgG immunoassay. RESULTS: Immunoenzymatic assay found anti-HEV antibodies (IgM and/or IgG) in blood serum samples obtained from 18 soldiers. Confirmatory tests were carried out among soldiers tested positive with ELISA or those with inconclusive test results; the confirmatory tests showed anti-HEV antibodies (IgM and/or IgG) in 16 of the studied soldiers, i.e. 6.3% of the study group. CONCLUSIONS: The occurrence of HEV infections in Polish soldiers justifies the need for the introduction of screening tests for HEV in the military environment, especially among blood donors and in cases of whole blood or blood products transfusion.

Detection of Giardia intestinalis infections in Polish soldiers deployed to Afghanistan.

BACKGROUND: Members of the Polish Military Contingent (PMC) have been stationed in Afghanistan since 2002. They typically serve in areas characterised by low standards of sanitation which often leads to the development of food- and waterborne diseases. The aim of the study was to evaluate the prevalence of Giardia intestinalis infections among Polish soldiers deployed to Afghanistan. The research study was conducted as part of a programme for prevention of parasitic diseases of the gastrointestinal tract run by the Polish Armed Forces. MATERIALS AND METHODS: The study was carried out in August 2011; it involved 630 asymptomatic Polish soldiers serving in the Forward Operational Base (FOB) Ghazni in eastern Afghanistan. Stool specimens obtained from members of the PMC were first tested in FOB Ghazni (detection of Giardia intestinalis by Rida Quick Giardia immunochromatographic tests and Ridascreen Giardia immunoenzymatic tests - single samples). Next, the same biological material and two other faecal specimens fixed in 10% formalin were transported to the Military Institute of Medicine in Poland, where they were tested for Giardia intestinalis under light microscopy (direct smear, decantation in distilled water). RESULTS: Parasitological tests performed under light microscopy showed that 2.7% (17/630) of the study group were infected with Giardia intestinalis. Some of these results were confirmed by immunochromatographic tests (6/630). In contrast, immunoenzymatic tests (ELISA) demonstrated a significantly higher detection rate reaching 18.1% (114/630). Immunoenzymatic tests confirmed all the positive results given by light microscopy and by immunochromatographic tests. CONCLUSIONS: The prevalence rate of Giardia intestinalis infections in Polish soldiers deployed to Afghanistan was found to be high. Microscopic methods exhibit low sensitivity and therefore may result in the underestimation of the true parasite prevalence. Immunoenzymatic tests (ELISA) showing a much higher sensitivity in comparison to light microscopy and immunochromatographic tests ought to be applied in screening for intestinal protozoan infections in areas characterised by harsh environmental conditions.

Respiratory tract infections in the military environment.

Military personnel fighting in contemporary battlefields as well as those participating in combat training are at risk of contracting respiratory infections. Epidemiological studies have demonstrated that soldiers deployed to the harsh environment have higher rates of newly reported respiratory symptoms than non-deployers. Acute respiratory diseases are the principle reason for outpatient treatment and hospitalization among military personnel, with an incidence exceeding that of the adult civilian population by up to three-fold. Adenoviruses, influenza A and B viruses, Streptococcus pneumoniae, Streptococcus pyogenes, coronaviruses and rhinoviruses have been identified as the main causes of acute respiratory infections among the military population. Although infective pathogens have been extensively studied, a significant proportion of illnesses (over 40%) have been due to unknown causative agents. Other health hazards, which can lead to respiratory illnesses among troops, are extreme air temperatures, desert dust, emissions from burn pits, industrial pollutants, and airborne contaminants originating from degraded soil. Limited diagnostic capabilities, especially inside the area of operations, make it difficult to accurately estimate the exact number of respiratory diseases in the military environment. The aim of the study was to discuss the occurrence of respiratory tract infections in army personnel, existing risk factors and preventive measures.

Occurrence of Chlamydia trachomatis in military environment on the example of professional soldiers in the Polish Armed Forces.

This article presents the results of a preliminary study concerning cases of Chlamydia trachomatis infections among professional soldiers in the Polish Armed Forces. Soldiers who declared casual sexual contact with women were investigated in this study regarding the transmission of chlamydial infections by sexual activity. In total, 66 healthy, sexually active professional Polish soldiers, aged between 27 and 44, who didn't report any symptoms of urogenital infection were investigated. Urine samples taken from these patients were investigated using molecular methods (Cobas TaqMan, real-time PCR) in March-April 2012 in the Military Institute of Medicine, Warsaw, Poland. In the investigated group of 66 Polish soldiers, two 33-34 year old men were asymptomatic carriers of Chlamydia trachomatis (3.0%). They confirmed having casual sexual activity without prevention with many women. In the examined group of Polish soldiers the relatively low level of chlamydial infections found may result from the use of preventive measures during sexual activity. According to the examined men, the common use of condoms is mainly connected with the fear of HIV infection. Screening tests for Chlamydia trachomatis in the Polish Armed Forces are not performed, therefore incidence rates of chlamydial infections remain unknown. The authors plan further investigations with a larger group of professional soldiers.