Objective: Assessment of diphtheria changing patterns in closed community with high IgG antibodies titres. Patients and methods: During 10 months of 2000, 221 persons were affected by diphtheria in Latvia. 149 patients (67.4%) of all affected came from a closed military higher school. This very group of patients was analysed. The patients were under 30 years of age, 95% of them were men, all of whom were vaccinated against diphtheria and on entering the higher school they had undergone the health examination confirming that everybody was healthy. The diagnosis of diphtheria was based on clinical data, establishment of Corynebacterium diphtheriae and the presence of specific IgM antibodies. Results: The clinical courses were estimated as severe in 2 cases, moderate - in 137, and mild in 10 cases. The carriers of C. diphtheriae were not found among the admitted patients at the in-patient department of the Infectology Center of Latvia. The causative agent was found in smears from nasopharyngeal cavity of 117 patients, IgM antibodies were established in 40 cases, and both the causative agent and the mentioned antibodies were found in 30 cases. The check of immune status confirmed that the immunograms were estimated at normal level only in 49.2% of the examined patients, a reduced CD4/CD8 ratio was found in 20%, and in the rest of the patients increased CD4/CD8 ratio was revealed. Antitoxic sera and antibacterials were used for the treatment of patients in compliance with WHO recommendations. A single course of antibiotics was sufficient only for 97 patients (65.1%), 41 patients (27.5%) received two courses of antibacterial therapy, and 11 patients (7.4%) got three courses of antibacterial therapy. A very substantial finding was the level of IgG antibodies, namely, above 1.0 IU/mL in 113 (5.8%) patients;up to0.1IU/mL-in 5 patients,0.3 IU/mL-in 8 patients,0.5 IU/mL-in6patients;0.7 IU/mL - in 4 patients, 1.0 IU/mL - in 9 patients. IgG antibodies were not found in 3 patients (2%). Conclusions: It is clear that the level of IgG antibodies, which has been considered to be sufficient till now, is not efficient for the protecting of people against diphtheria in closed communities. It is advisable to reconsider the treatment recommendations and to consider a rational antibacterial therapy: either antibacterials of two different groups, or a longer course of therapy.
Full conference title:
11th European Congress of Clinical Microbiology and Infectious Diseases
- ECCMID 11th (2001)