Doses Of Whole-cell Pertussis Vaccine Research Articles

Indian Academy of Pediatrics (IAP) recommended immunization schedule for children aged 0 through 18 years--India, 2014 and updates on immunization.

There is a need to review/revise recommendations about existing vaccines in light of recent developments in the field of vaccinology. Following an IAP ACVIP meeting on April 19 and 20, 2014, a draft of revised recommendations for the year 2014 and updates on certain vaccine formulations was prepared and circulated among the meeting participants to arrive at a consensus. To review and revise recommendations for 2014 Immunization timetable for pediatricians in office practice and issue statements on certain new and existing vaccine formulations. The major changes in the 2014 Immunization Timetable include two doses of MMR vaccine at 9 and 15 months of age, single dose recommendation for administration of live attenuated H2 strain hepatitis A vaccine, inclusion of two new situations in high-risk category of children in context with pre-exposure prophylaxis of rabies, creation of a new slot at 9-12 months of age for typhoid conjugate vaccine for primary immunization, and recommendation of two doses of human papilloma virus vaccines with a minimum interval of 6 months between doses for primary schedule of adolescent/preadolescent girls aged 9-14 years. There would not be any change to the committee's last year's (2013) recommendations on pertussis vaccination and administration schedule of monovalent human rotavirus vaccine. There is no need of providing additional doses of whole-cell pertussis vaccine to children who have earlier completed their primary schedule with acellular pertussis vaccine-containing products. A brief update on the new Indian Rotavirus vaccine, 116E is also provided. The committee has reviewed and offered its recommendations on the currently available pentavalent vaccine (DTwP+Hib+Hepatitis-B) combinations in Indian market. The comments and footnotes for several vaccines are also updated and revised.

Evaluation of pertussis immunity status in schoolchildren immunized with whole-cell vaccine

It has recently been reported that the worldwide increase in the number of pertussis cases is a result of the waning of whole-cell vaccine-induced immunity. Thus, in this study, we aimed to investigate the pertussis immunity status of primary and secondary school students in a district of Ankara, Turkey. A total of 997 healthy students, aged 9-17 years, who had been immunized with four doses of whole-cell pertussis vaccine were included in the study. The subjects were divided into two age groups: 9-14 and 15-17 years. To determine the immune status, serum levels of IgG anti-pertussis toxin (aPT) antibody were tested by in-house ELISA and arbitrarily evaluated as non-immune [< 10 ELISA units (EU)/ml], immune (10-100 EU/ml), and recent infection (> 100 EU/ml). Serum samples of 997 students (559 females, 438 males) aged between 9 and 17 years (mean 13.02 +/- 2.25, median 13 years) were tested. Non-immune, immune and recent infection levels of aPT were found in 27.3%, 59.3% and 13.4% of individuals, respectively. The immune group did not have statistically significant differences between males and females (P = 0.68). In the 9-14 and 15-17 years age groups, serum aPT antibody levels 10 EU/ml were 73.1% and 72.2%, respectively, which did not represent any statistical difference (P = 0.81). Students aged 15-17 years had a higher immunity rate than the 9-14 years group, and the percentage of students with recent infection in the 9-14 years group was higher than the 15-17 years group (P < 0.001). The peak age of non-immunized subjects was 9 years (47.0%), and decreased to a minimum at age 12-13 years, and began to increase again from age 13-14 years. In contrast, the ratio of recent infection was least at age 9-10 years, began to increase, and reached a peak at 12 years, and then decreased. On the other hand, it was observed that household size and monthly income were not associated with the immunity status (P = 0.65, P = 0.37, respectively). The results of the present study show that levels of antibody against pertussis decreased in the younger age groups and, as a result, there is an increase in the number of pertussis cases. Thus, in order to decrease the incidence of pertussis and protect infants, we recommend the application of booster doses at regular intervals.

Reactogenicity and immunogenicity of reduced antigen content diphtheria–tetanus–acellular pertussis vaccine (dTpa) administered as a booster to 4–6 year-old children primed with four doses of whole-cell pertussis vaccine

A trial to compare the reactogenicity and immunogenicity of a reduced antigen content diphtheria–tetanus–acellular pertussis (dTpa) vaccine with diphtheria–tetanus–whole-cell pertussis (DTPw) vaccine was conducted in Thailand. Three hundred and thirty children aged 4–6 years, primed with four doses of DTPw, received a single injection of either dTpa or DTPw. There was a significantly lower incidence of local and general reactions following dTpa than DTPw ( P<0.001). One month after vaccination, 99.4 and 100% of all subjects had protective anti-diphtheria and -tetanus titers, respectively. The vaccine response rate to pertussis antigens was similar in both groups, with 96.9% versus 92.5% for anti-pertussis toxin (PT), 96.9% versus 97.5% for anti-filamentous hemagglutinin (FHA) and 95.1% versus 90.8% for anti-pertactin (PRN) in the dTpa and DTPw groups, respectively. For anti-BPT, the vaccine response in the dTpa group was 29.6% versus 94.4% for DTPw. In conclusion, the dTpa vaccine was as immunogenic and significantly better tolerated than DTPw. The new dTpa vaccine could improve coverage for routine booster vaccination in children and provide a good replacement for DTP vaccines at 4–6 years of age.

Nature, evolution, and appraisal of adverse events and antibody response associated with the fifth consecutive dose of a five-component acellular pertussis-based combination vaccine

We performed a randomized, controlled clinical trial to characterize the evolution of the adverse events associated with the fifth consecutive dose of an acellular pertussis vaccine, and to assess the level of discomfort associated with the injection and the attitude of parents concerning these events. A total of 505 children who had received either four doses of acellular pertussis vaccine or whole-cell pertussis vaccine were given a fifth dose of one of the two vaccines. Adverse events were monitored by parents and collected by telephone or home visit at 4, 8, 12, 24, 48 and 72 h, and 7 and 28 days after immunization. Rates of injection site redness ≥50 mm were similar in recipients of five doses of acellular pertussis vaccine (32.8%) or five doses of whole-cell pertussis vaccine (43.3%). Injection site swelling, tenderness, and decreased arm movement were all more frequent in children who received five doses of whole-cell pertussis vaccine. Antibody levels before or after immunization did not predict those children who had increased injection site reactions. The children rated the injection site reactions as significantly more severe after five consecutive doses of whole-cell vaccine. Parent satisfaction was higher after the acellular vaccine. We conclude that a fifth consecutive dose of a whole-cell pertussis vaccine is associated with high rates of tender redness and swelling at the injection site, in contrast to a fifth consecutive dose of an acellular pertussis vaccine which is associated with high rates of non-painful redness. However, parents will still need to be aware of the high rates of injection site reactions expected after a fifth dose of acellular pertussis vaccine.

Reputed Brain Damage and 'Serious' Reactions From DTP Vaccines-Reply

We disagree with Dr Sepkowitz that examining the Vaccine Adverse Event Reporting System for rare serious events casts doubt on the safety of vaccines. Demonstrating that reported adverse events after the the administration of the acellular pertussis vaccine are (1) rare after millions of doses have been used (vs only thousands used in prelicensure clinical trials) and (2) less common than similar events reported after the administration of the whole-cell pertussis vaccine should help instill public confidence in a vaccine that historically has been the most feared. While controversy remains about whether the whole-cell pertussis vaccine has been proven to be a cause of permanent neurologic damage, 1-3 a consensus exists that the evidence is consistent with a causal relationship between the whole-cell pertussis vaccine and acute encephalopathy, with an attributable risk between 0 and 10.5 cases per million doses of whole-cell pertussis vaccine. 4 As Dr Sepkowitz

ACELLULAR PERTUSSIS VACCINE: A NEW ERA FOR INFANTS.

In the U.S., infants under one year old receive three doses of whole-cell pertussis vaccine, which is effective but has numerous adverse effects. Two

Proliferative response of immune mouse T-lymphocytes to the lymphocytosis-promoting factor of Bordetella pertussis.

Immunization of mice with a whole-cell pertussis vaccine or with the purified, detoxified lymphocytosis-promoting factor (LPF) of Bordetella pertussis resulted in an increased in vitro proliferative response to LPF in immune lymph node cells. The proliferative response was detected above the nonspecific mitogenic activity of LPF. That the proliferative response of the immune lymph node cells was a demonstration of a specific cell-mediated immunity to LPF was supported by the following: (i) the specificity of the response to the immunizing antigen; (ii) the ability of chemically modified, nonmitogenic LPF to induce proliferation in immune lymph node cells; and (iii) a dependence on T-cells for the demonstration of the proliferative response of immune cells to LPF. Immunization of mice with protective doses of detoxified LPF resulted in serum antibody and cell-mediated responses to LPF. Immunization of mice with protective doses of whole-cell pertussis vaccine resulted in a cell-mediated response but not a detectable antibody response to LPF. The LPF of B. pertussis is believed to play an important role in pathogenesis and immunity in pertussis, and the demonstration of a cell-mediated immune response to LPF suggests a possible role for cell-mediated immunity to LPF in protection from pertussis disease.