Natural course of 500 consecutive cases of whooping cough: a general practice population study.

OBJECTIVE--To describe the natural course of whooping cough. DESIGN--Observational study of a general practice population. SETTING--Discrete semirural East Midlands practice of 11,500 patients. SUBJECTS--500 consecutive cases of whooping cough diagnosed clinically during 1977-92. MAIN OUTCOME MEASURES--Incidence of vomiting, whooping, apnoea, admission to hospital, and complications; duration and frequency of paroxysms. Pattern of spread. RESULTS--The incidence in the practice population was 4347/100,000 population compared with a notification rate for England and Wales of 717/100,000. Most cases were relatively mild. 284 patients vomited after paroxysms, 242 whooped, and 57 had apnoea. Duration and frequency of paroxysms varied widely. Female and unimmunised patients suffered more severe disease. Bordetella was isolated from fewer immunised patients (24/96 v 63/122 unimmunised). Infection was usually spread through contacts with someone with clinical whooping cough. Five patients developed pneumonia, three of whom had been immunised. Three patients required hospital admission. CONCLUSIONS--Most cases of whooping cough are relatively mild. Such cases are difficult to diagnose without a high index of suspicion because doctors are unlikely to hear the characteristic cough, which may be the only symptom. Parents can be reassured that a serious outcome is unlikely. Adults also get whooping cough, especially from their children, and get the same symptoms as children. The difficulty of early diagnosis and probability of missed cases reinforces the need to keep the incidence low through immunisation in order to protect infants, who are the most vulnerable.     

Respiratory sequelae of whooping cough. Swansea Research Unit of the Royal College of General Practitioners.

Eight hundred and thirteen children who had had whooping cough when under 5 years of age in the 1977-9 epidemic were compared with a control group roughly four and a half years later, each child being matched by age and sex and from the same class in school. The index group showed long term respiratory sequelae of whooping cough--namely, deterioration in lung function, increase in respiratory symptoms, and increased admission to hospital for both upper and lower respiratory conditions. Asthma was significantly more common in the index group, suggesting that asthma was being regarded as a contraindication to pertussis vaccination. Only 3.5% of the asthmatic children in the index group had been vaccinated as against 29.1% of the controls.     

Whooping cough after stopping pertussis immunisation.

An epidemic of whooping cough occurred in a rural practice in Shetland, containing 144 children under 16. Before July 1974 all children were immunised against pertussis, but after that date immunisation was stopped. Of the 134 children studied, 93 had been immunised. Sixty-five of the children developed whooping cough. The incidence of infection was similar in those who had and had not been immunised. The incidence was also similar in those born before and after July 1974. There was no evidence to support the routine use of pertussis immunisation in rural Shetland.     

Attack rates of notified whooping cough in immunised and unimmunised children.

The incidence of whooping cough among immunised children under the age of six and among children of the same age who were not fully immunised was ascertained by analysing whooping-cough notifications from several health authorities. In the first three years of the study the results showed that attack rates were much higher in children who were not fully immunised than in those who were. This finding suggests that current vaccines provide young children with substantial protection against whooping cough.     

Febrile convulsions in a national cohort followed up from birth. II--Medical history and intellectual ability at 5 years of age.

Three hundred and three children with febrile convulsions were identified in a national birth cohort of 13 135 children followed up from birth to the age of 5 years. Breech delivery (p less than 0.05) was the only significantly associated prenatal or perinatal factor. There were no associations with socioeconomic factors. Excluding the 13 known to be neurologically abnormal before their first febrile convulsion, children who had had a febrile convulsion did not differ at age 5 from their peers who had not had febrile convulsions in their behaviour, height, head circumference, or performance in simple intellectual tests.     

Injury by hypertonic phosphate enema.

Over a 2-year period 67 strains of Bordetella pertussis were identified in 231 single specimens of nasopharyngeal secretions submitted from patients suspected to have whooping cough in the National Capital Region; 89.5% of the identifications were made by culture. Serotype 1,3 was predominant. At least 75% of the patients with bacteriologically confirmed whooping cough had not been fully immunized. There was no evidence that adenoviruses or other viruses played any important etiologic role in the 204 cases of whooping cough or whooping cough syndrome studied virologically.     

Etiology, clinical manifestations, and epidemiology in community-acquired respiratory infection in children in the Khabarovsk region

Clinico-epidemiological analysis and etiological verification of the outbreak of respiratory infection among school children in a rural district of the Khabarovsk territory, registered in spring 1997, were made. According to clinical signs, one-third of the patients had whooping cough, while the rest of the children exhibited the signs of respiratory infection with the symptoms of longering bronchitis. A half of the children had not been vaccinated against whooping cough, as they had been given injections of adsorbed DT vaccine with reduced antigen content. Etiologically, the diagnosis of whooping cough was confirmed in 57% of the patients with 47.4% of them having Bordetella pertussis monoinfection and 52.6% having mixed infection, mainly in combination with chlamydiosis. Whooping cough took an abnormal course under these circumstances. Treatment with erythromycin produced a good effect.     

Effect of vaccination on severity and dissemination of whooping cough.

A study was undertaken in general practice to clarify those factors, especially vaccinations, that influence the clinical picture and infectivity of whooping cough in the community. Although the range of the disease encountered was fairly mild, its duration was notable (mean +/- SD 50.9 +/- 32.1 days). By using multiway contingency table analysis it was found that in the more severe cases of whooping cough vaccination significantly shortened the illness (p less than 0.005) and reduced the number of coughing spasms (p less than 0.025). The protective effect of the vaccine was most notable in modifying infectivity within the family: 19% of vaccinated family contacts of index patients in whom the disease had been confirmed bacteriologically developed the disease when exposed to it compared with 72% of non-vaccinated contacts (p less than 0.001). These results show that whooping cough vaccination modifies the clinical illness and offers a worthwhile degree of protection to children exposed to the disease.     

Impact of whooping cough on patients and their families.

The effects of whooping cough were studied in 21 children admitted to hospital with the disease and in their families. The illness caused considerable distress to both child and family. Parents suffered especially from fears for the life and health of their child and from serious loss of sleep. Two months after admission the child''s behaviour was still disturbed, but in most cases the rest of the family had returned to normal. There was much misunderstanding and misinformation about whooping cough among both parents and doctors.     

Whooping cough in adults.

During the 1970s whooping cough returned in Sweden after an absence of more than 10 years and is now seen in all age groups, During a three-year period 174 adults with culture-verified whooping cough were identified in Gothenburg. Most of the patients had typical symptoms with whooping attacks and often vomiting. The disease was long lasting but complications were rare. Physicians should be aware that whooping cough may occur in adults, since adults may be an important source of infection for infants and erythromycin given in the catarrhal phase may modify the clinical course.     

Outcome of childhood status epilepticus and lengthy febrile convulsions: findings of national cohort study.

OBJECTIVE--To study outcome after lengthy febrile convulsions and status epilepticus in children. DESIGN--Population based birth cohort study. SETTING--The child health and education study (16,004 neonatal survivors born in one week in April 1970). SUBJECTS--Information available for 14,676 children. OUTCOME MEASURES--Clinical information and tests of intellectual performance at five and 10 years after birth. RESULTS--19 children had lengthy febrile convulsions and 18 had status epilepticus. Two children with status epilepticus died (one at 5 years old); neither death was directly due to the status epilepticus. Four of the 19 (21%) developed afebrile seizures after lengthy febrile convulsions compared with 14 of the 17 (82%) survivors after status epilepticus. Measures of intellectual performance were available for 33 of the 35 survivors: 23 were normal and 10 were not normal but eight of them had preceding developmental delay or neurological abnormality. CONCLUSION--The outcome in children after lengthy febrile convulsions and status epilepticus is better than reported from studies of selected groups and seems determined more by the underlying cause than by the seizures themselves.     

Severity of notified whooping cough.

An analysis was made of the severity of over 8000 cases of whooping cough notified from October 1974 to March 1975. Ten per cent of these patients were admitted to hospital and there were 10 deaths. Severity was directly related to age, the disease being most severe in children under 1 year, especially those under 6 months. There was some evidence that previous vaccination reduced the severity of the disease, but the vaccination programme does not cover very young children, and for them whooping cough is a dangerous disease.     

Protection against pertussis by immunisation.

Review of all 126 children admitted to the communicable diseases unit with whooping cough during the epidemic in 1978 showed that two had received two doses of triple vaccine and only one had had full primary immunisation against the disease. None of these three children suffered complications of the disease. Of the 123 children who had not been immunised against pertussis, however, 66 had had one or more complications. In Birmingham the dramatic decline in immunisation against pertussis has been accompanied by a fall in acceptance rates for diphtheria and tetanus immunization. Nevertheless, of the 62 children aged over 1 year in this series, 41 had been so immunised. These findings suggest that the apparently positive decision by parents to omit pertussis immunisation was misplaced, since immunisation does protect against the more serious complications of the disease. Furthermore, there is no firm evidence that pertussis immunisation of children without specific contraindications is associated with serious adverse reactions.     

Duration of effectiveness of pertussis vaccine: evidence from a 10 year community study

A 10 year study of whooping cough in a discrete general practice community was performed to assess longitudinally the efficacy of pertussis vaccine from one to seven years after immunisation. Of the 436 cases of whooping cough over 10 years, 326 occurred in children aged 1-7 years. The rate of immunisation was known for each cohort of children born during each year, and the attack rate of whooping cough was thus calculated for those immunised and unimmunised. The attack rates were highest in those cohorts exposed to the epidemics of 1977-9, 1981-3, and 1985-7. The efficacy of the vaccine was calculated as a percentage as (attack rate in unimmunised group—attack rate in immunised group) × 100/attack rate in unimmunised group. It fell from 100% in the first year to 46% in the seventh, being 84% in the fourth and only 52% in the fifth.Thus the pertussis vaccine or its schedule of use does not seem to provide sufficient herd immunity to prevent outbreaks of whooping cough. Matters might be improved if vaccination against pertussis were included in the preschool immunisation programme.     

Domiciliary immunisation for preschool child defaulters.

A selective domiciliary immunisation service has been introduced for preschool children living in the Central Manchester Health District. The service is provided for the children of parents who have given written consent for immunisation but have subsequently failed to bring their children to the clinic or their general practitioner''s surgery to start or complete the basic course of immunisation against diphtheria, tetanus, whooping cough, poliomyelitis, and measles. This failure has occurred despite at least two written invitations for each injection and several reminders from the health visitor. Many additional children have been protected by this scheme.     

Intensity of the epidemic process of whooping cough under conditions of mass immunization over a period of many years

On the basis of analysis of whooping cough incidence in 1959 to 1975 in Moscow the authors present characteristics of the epidemic process under conditions of planned many-year immunization of children against this infection. Whooping cough morbidity proved to undergo significant changes-from sharp falls the first 8 years of immunization to a relative stabilization with a gradual reduction the last 5 years. Marked seasonal and periodic elevations persist against the background of reduction of morbidity. Preschool- and schoolchildren are equally involved in the epidemic process; the most frequently involved are nonvaccinated children aged 1 year and 4 to 10 years, which lost postvaccinal immunity. Further reduction of the severity of whooping cough and increase in the number of unimanifested forms of the infection was noted. This was apparently connected not only with immunization, but also with the reduction of the virulence of H. pertusis detected in studying the cultures isolated in Moscow from 1967 to 1974. The intensity indices of the epidemic process in whooping cough pointed to the necessity of using a more effective vaccine for the protection of children from whooping cough, despite the noted reduction of morbidity, and diminished severity of the course of the disease, and of the causative agent virulence.     

Humoral reaction to Bordetella pertussis antigens: pertussis toxin, filamentous hemagglutinin and lipopolysaccharide in children with clinical symptoms of whooping cough. II. Occurence and level of B. pertussis antigens in children with suspected whooping cough

The aim of this study was to determine and evaluate IgG, IgM and IgA levels to pertussis toxin (PT), filamentous hemagglutinin (FHA) and endotoxin (LPS) of B. pertussis in children with clinical symptoms of whooping cough. The serum samples obtained from 265 children (age range: 2 months-16 years) suspected of pertussis were examined by indirect haemagglutination (IH) and ELISA tests. Higher antibody level was most frequently observed in IgA class to PT, FHA and LPS in 45.3%, 35.1% and 66% of pertussis patients sera respectively. The least positive results were obtained in IgM class to PT and FHA (in 9.8% and 2.6% of children sera respectively) but in the case of LPS applied as the antigen in ELISA, higher IgM level was determined in 46.8% of pertussis patients sera. The four times increase of antibody level to LPS determined by IH was observed in 86.7% of children suspected of pertussis. Humoral response to B. pertussis infection is mainly connected with higher IgA level to PT, FHA, LPS and IgM to LPS in children with clinical symptoms of whooping cough.     

Growth retardation in weight and catch-up growth following infection by measles and whooping cough among babies of rural Zaire (Lake Tumba)

This study has shown that measles and whooping cough affect growth in weight among babies of rural Zaire (Lake Tumba). The average loss in weight due to measles, is more than twice the amount due to whooping cough. However, the time needed to regain the original growth channel after infection by measles, is about half the time needed to fully catch up after whooping cough. The amount of weight loss is proportional to the child's weight at the onset of the disease. There is no difference in the susceptibility to lose weight after measles or whooping cough, between boys and girls, nor between Oto and Twa. This study has also shown that the effect of measles and whooping cough on the growth in weight, is independent of the season of the hear, although the incidence of these diseases showed a significant seasonal pattern. Finally, this study gives evidence for the fact that the incidence of weight loss one month after the onset of measles or whooping cough is age-related.     

Failure of phenobarbitone to prevent febrile convulsions.

One-hundred-sixty-five children without known neurological disorder who presented with their first febrile convulsion between the ages of six months and three years were assigned to daily phenobarbitone treatment or to a control group and followed up at a special clinic for six months. One-hundred-and-sixty-one-one children completed the trial, and of the 88 children assigned to phenobarbitone treatment 10 had further convulsions during this period compared with 14 of the 73 control children. Only 49 of those assigned to phenobarbitone took the drug regularly throughout the trial, and four of these had further febrile convulsions, a proportion not significantly different from that in the controls. All four had mean plasma phenobarbitone concentrations over 69 mumol/l (16 mug/ml) during the trial and in three the plasma concentration was at or over this figure within eight hours over 69 mumol/l (16 mug/ml) during the trial and in three the plasma concentration was at or over this figure within eight hours of the repeat convulsion. Regular phenobarbitone does not seem to prevent febrile convulsions. Attention should instead be directed to organising emergency services to allow early termination of fevrile convulsions, whether first or subsequent, to prevent irreversible brain damage.     

Epilepsy in childhood: findings from the National Child Development Study.

By the age of 11 years 1043 children (6.7%) in an unselected national sample had a history of seizures or other episodes of loss of consciousness; 322 (20.8/1000) had a history of febrile convulsions without other epileptic problems. A clear-cut diagnosis of non-febrile epilepsy was established in 64 children (4.1/1000) by the age of 11 on the basis of confirmatory information supplied by family doctors and paediatricians. A further 39 (2.6/1000) were reported as having epilepsy but did not fulfil the study criteria. The progress of 59 of the 64 children with estabished epilepsy was reviewed again when they were aged 16. Of the 37 educated in normal schools eight (22%) had one or more seizures in their 16th year compared with 13 out of 22 (59%) who received special education. A possible cause for epilepsy was found in 17 of the 64 (27%) children, but for the majority there was no obvious reason.