Reporting vaccine-associated paralytic poliomyelitis: concordance between the CDC and the National Vaccine Injury Compensation Program

Novel BTK mutation presenting with vaccine-associated paralytic poliomyelitis

Oral polio vaccine (OPV) has been used safely and efficiently for more than 40 years in preventive medicine. Vaccine-associated paralytic poliomyelitis (VAPP) is a rare adverse event of OPV due to reversion of the vaccine strain virus to a neurovirulent strain. VAPP can occur in healthy recipients or their close contacts. However, persons with primary humoral immunodeficiencies are at a much higher risk. X-linked agammaglobulinemia (XLA) is a prototypic humoral deficiency caused by mutations in the Bruton's tyrosine kinase (BTK) gene. In addition to susceptibility to bacterial infections, patients with XLA are especially prone to enteroviruses. Here, we describe the occurrence of VAPP in a 15-month old Iranian boy. The child had received four doses of OPV, administered at birth, 2, 4, and 6 months of age. The patient's infectious history was unremarkable. Laboratory evaluation revealed low levels of immunoglobulin G and CD19(+) B cells of less than 1% of the lymphocyte population. A novel insertion (c.685_686insTTAC) in the SH3 domain of the BTK gene was detected as the underlying cause. Immunodeficient recipients of OPV can excrete poliovirus vaccine strains for a long period and are at risk of developing flaccid paralysis. They could also serve as a source of reverted virulent poliovirus to be reintroduced into the general population. This patient presented for the first time with VAPP, without any history of other major infections in 15 months. This suggests that a negative history for recurrent infections does not exclude the presence of a primary defect in the immune system.

Infant immunization with acellular pertussis vaccines in the United States: assessment of the first two years' data from the Vaccine Adverse Event Reporting System (VAERS)

OBJECTIVE

To evaluate the safety of infant immunization with acellular pertussis vaccines in the United States.

BACKGROUND

The US Food and Drug Administration approved the first acellular pertussis vaccine for use in infants in the United States on July 31, 1996.

OUTCOME MEASURES

Adverse events in the United States after infant immunization with pertussis-containing vaccines, representing temporal (but not necessarily causal) associations between vaccinations and adverse events.

DATA SOURCE

Reports to the Vaccine Adverse Event Reporting System (VAERS), a passive national surveillance system.

DESIGN

Reports concerning infant immunization against pertussis between January 1, 1995 (when whole-cell vaccine was in exclusive use) and June 30, 1998 (when acellular vaccine was in predominant use) were analyzed, if the reports were entered into the VAERS database by November 30, 1998.

RESULTS

During the study, there were 285 reports involving death, 971 nonfatal serious reports, and 4514 less serious reports after immunization with any pertussis-containing vaccine. For 1995 there were 2071 reports; in 1996 there were 1894 reports; in 1997 there were 1314 reports, and in the first half of 1998 there were 491 reports. Diphtheria-tetanus-pertussis vaccine (DTP) was cited in 1939 reports, diphtheria-tetanus-whole-cell pertussis-Haemophilus influenzae type b vaccine (DTPH) in 2918 reports, and diphtheria-tetanus-acellular pertussis vaccine (DTaP) in 913 reports. The annual number of deaths during the study was 85 in 1995, 82 in 1996, 77 in 1997, and 41 in the first half of 1998. The annual number of reported events categorized as nonfatal serious (defined as events involving initial hospitalization, prolongation of hospitalization, life-threatening illness, or permanent disability) to VAERS for all pertussis-containing vaccines declined: 334 in 1995, 311 in 1996, 233 in 1997, and 93 in the first half of 1998. Similarly, the annual number of less serious reports to VAERS for pertussis-containing vaccines declined: 1652 in 1995, 1501 in 1996, 1004 in 1997, and 357 in the first half of 1998. A comparison of the adverse event profiles (proportional distributions) for DTaP, DTP, and DTPH, as well as an analysis of specific adverse events considered in a 1991 Institute of Medicine report on the safety of diphtheria-tetanus-pertussis vaccine, did not identify any new, clear safety concerns.

CONCLUSIONS

These findings reflect the administration of millions of doses of acellular pertussis vaccine and are reassuring with regard to the safety of marketed acellular pertussis vaccines. VAERS data, although subject to the limitations of passive surveillance, support the prelicensure data with regard to the safety of the US-licensed acellular pertussis vaccines that we evaluated.

Vaccine-associated paralytic poliomyelitis: a retrospective cohort study of acute flaccid paralyses in Brazil

BACKGROUND

At the present time, in Brazil and other countries in the Americas, the only cases of paralytic poliomyelitis due to poliovirus are caused by vaccine strains. The recognition of possible determinants of vaccine-associated paralytic poliomyelitis (VAPP) by public health surveillance and immunization programmes is relevant to inform the debate on criteria for case definition and vaccination strategies.

METHODS

A retrospective cohort study based on the cases of acute flaccid paralysis (AFP) reported to the Ministry of Health (MoH) was designed, with the objective of studying cases of VAPP in Brazil between 1989 and 1995. Clinical, laboratory and epidemiological data from 3656 acute flaccid paralysis (AFP) cases, 30 of them diagnosed as VAPP, were analysed.

RESULTS

An 8.88 risk ratio of VAPP (95% CI : 4.37-18.03) was found when comparing individuals who received oral poliovirus vaccine (OPV) between 4 and 40 days before the onset of paralysis and individuals who did not receive the vaccine within this period. A risk of 1 case/2.39 million first doses and 1 case/13.03 million OPV doses administered was estimated for the general population.

CONCLUSIONS

Cases of AFP who received OPV between 4 and 40 days before the onset of paralysis and had fever, a prodrome of gastrointestinal symptoms, history of first dose of OPV, isolation of vaccine poliovirus type 2, and young age deserve careful investigation, since they are at increased risk for the condition studied.

Role of provocation poliomyelitis in vaccine-associated poliomyelitis

The impact of different vaccine administrations in the Federal Republic of Germany, in relation to vaccine-associated paralytic poliomyelitis (VAPP) was studied. (This only means that on the basis of the temporal relation of vaccination and onset, the vaccine cannot be ruled out as possible cause). Oral polio vaccine (OPV) was given between 1963 and 1977 only and recommended simultaneously with inactivated vaccines (DT/DPT) between 1980 and 1985. In the first period 10 VAPP cases occurred among 9.96 million estimated vaccinees aged under 2 years. In the second period 6 cases of provocation poliomyelitis (PRP) were found among 2.9 million estimated OPV/DT/DPT vaccinees of the same age group. Statistically the VAPP/PRP frequencies in the two periods studied did not achieve significance.