There are limited clinical and epidemiological data on patients diagnosed with Bell's palsy. While investigating an apparent clustering of Bell's palsy, we sought to characterize the spectrum of illness in patients with this diagnosis.
A telephone survey of persons with idiopathic facial (Bell's) palsy in the Greater Toronto Area (GTA, population = 4.99 million) and Nova Scotia (population = 0.93 million) from August 1 to November 15, 1997 collected information on subject demographics, neurological symptoms, constitutional symptoms, medical investigation and management. Information regarding potential risks for exposure to infectious agents, past medical history, and family history of Bell's palsy was also collected. Subjects with other secondary causes of facial palsy were excluded.
In the GTA and Nova Scotia, 222 and 36 patients were diagnosed with idiopathic facial (Bell's) palsy, respectively. The crude annualized incidence of Bell's palsy was 15.2 and 13.1 per 100,000 population in the GTA and Nova Scotia, respectively. There was no temporal or geographical clustering, and symptomatology did not differ significantly between the two samples. The mean age was 45 years, with 55% of subjects being female. The most common symptoms accompanying Bell's palsy were increased tearing (63%), pain in or around the ear (63%), and taste abnormalities (52%). A significant number of patients reported neurological symptoms not attributable to the facial nerve.
No clustering of cases of Bell's palsy was observed to support an infectious etiology for the condition. Misdiagnosis of the etiology of facial weakness is common. Patients diagnosed with Bell's palsy have a variety of neurological symptoms, many of which cannot be attributed to a facial nerve disorder.
Pertussis deaths occur primarily among infants who have not been fully immunised. In Ontario, Canada, an adult booster dose was recently added to the publicly funded immunisation programme. We applied number-needed-to-treat analyses to estimate the number of adults that would need to be vaccinated (NNV) to prevent pertussis disease, hospitalisation and death among infants if a cocoon strategy were implemented. NNV=1/(P(M) X R) + 1/(P(F) X R), where P(M),P(F) (proportion of infants infected by mothers, fathers) were sourced from several studies. Rates of disease, hospitalisation or death (R) were derived from Ontario's reportable disease data and Discharge Abstract Database. After adjusting for under-reporting, the NNV to prevent one case, hospitalisation or death from pertussis was between 500-6,400, 12,000-63,000 and 1.1-12.8 million, respectively. Without adjustment, NNV increased to 5,000-60,000, 55,000-297,000 and 2.5-30.2 million, respectively. Rarer outcomes were associated with higher NNV. These analyses demonstrate the relative inefficiency of a cocoon strategy in Ontario, which has a well-established universal immunisation programme with relatively high coverage and low disease incidence. Other jurisdictions considering a cocoon programme should consider their local epidemiology.
Comment In: Euro Surveill. 2014;19(5). pii: 2068924524233
Ontario initiated a universal hepatitis B immunization program for grade seven students in the fall of 1994. An ecological study was conducted within seven health units of the Greater Toronto Area to assess vaccine coverage. The study population consisted of all grade seven students enrolled within schools in the participating health units, on October 1, 1994. There were 39,935 students enrolled in 604 schools eligible for inclusion in the study. Consent to receive the vaccine series was obtained for 88% (range across health units from 81.5% to 96.3%) of the students. Among students for whom consent was obtained, an average of 95% (range 88.1% to 99.5%) completed the series. Therefore, the total vaccine coverage for the study population was 84% (range 77.5% to 89.5%). Series completion varied by school board, education provider and the use of Ministry of Health educational material. A limiting factor in achieving high vaccination coverage among grade seven students was obtaining consent to receive the vaccine series.