| Área: Imunologia ( Divisão E ) DIPHTHERIA ANTITOXIN IGG LEVELS IN MILITARY AND CIVIL BLOOD DONORS FROM RIO DE JANEIRO, BRAZIL
Francisco Almeida Braga Speranza (UERJ); Louisy Sanches dos Santos (UERJ); Solange Kiyoko Ishii (MEX); Raphael Hirata Junior (UERJ); Ana Luiza de Mattos-guaraldi (UERJ); Lucimar Gonçalves Milagres (UERJ)
ResumoDiphtheria is a life-threatening
disease that can be prevented through immunization. The recommended vaccination
schedule in Brazil consists of three doses of diphtheria-tetanus-pertussis
vaccine (DTP) in the first year of life, followed by a booster dose at 5-6
years of age. In 2002, the Public Health Agency of Rio de Janeiro (SES-RJ 2002)
stated a shifting in the age distribution of cases of diphtheria to persons
over 15 years of age. Current information also indicated the circulation of Corynebacterium
diphtheriae in our population, including cancer patients and healthy
vaccinated adults. In response to the huge epidemic that hit the countries of
the Russian confederation, since 2004 the Brazilian Ministry of Health
recommended an additional diphtheria-tetanus booster dose to be provided every
subsequent 10 years. Serologic data on diseases that are preventable by vaccine
are useful to evaluate the success of immunization programs and to identify
susceptible subgroups. However, there are few published data regarding regular
immunization coverage and immunity of Brazilian adult population. A previous survey
carried out on serum samples collected from blood donors of a universitary
hospital of Rio de Janeiro from July to October 2002 showed that a high
proportion (~70%) of individuals from 18 to 30 years of age had non-protective
antibody levels against the diphtheria toxin. Considering the potential risk of
low antibody levels, these data highlight the need for additional
seroepidemiological surveys in Brazil. Due to the possibility of outbreaks of
respiratory diphtheria among military, several studies have been performed in
order to assess the immune status against diphtheria of soldiers in different
countries. In
Brazil, little is known about antibody levels against the diphtheria toxin in
individuals joining military service. In
this report we determined serum IgG levels to diphtheria toxin of military and
civil blood donors, aged 18-64 years, from
the Brazilian Army Biology Institute, Rio
de Janeiro, using a commercial diphtheria-ELISA kit. Most
(63.6%) unprotected militaries were from the older age group; 33 to 64 years.
In contrast, the majority (72%) of young militaries (18 to 32 years) were fully
protected. Concerning to the civilians, 50% of persons from 18 to 32 years had
protective antibody levels to diphtheria as well 52% of individuals aged 33 to
64 years. Civilians had similar antibody response (mean of 0.66 IU/ml)
independent of the age group. Militaries of 18-32 years had high IgG levels (mean
of 0.87 IU/ml) than militaries of 33-64 years (mean of 0.59 IU/ml) (P = 0.03). Concluding, the existence of susceptible military and civilian adults creates an
epidemic potential in our community and reinforces that reliable data on the immune status of the population should be
routinely maintained. Financial support: CNPq, CAPES, FAPERJ, SR-2/UERJ
Palavras-chave: Diphtheria, Diphtheria antitoxin, Rio de Janeiro |