Laboratory reports of Haemophilus influenzae by age group and serotype: England and Wales, April to June 2014
Updated 27 February 2015
In the second quarter of 2014 (April to June) there were a total of 206 laboratory reports of invasive Haemophilus influenzae. This represents a 16% decrease in cases compared to the previous quarter (n=206) and a 24% increase compared to the second quarter of 2013 (n=140).
Of the samples which underwent serotyping (n=142), 84% were non-capsulated Haemophilus influenzae (ncHi), a further 12% were serotype a, e, or f, and 4% were serotype b (Hib). These results indicate a slight decrease in the proportion of ncHi cases compared to the second quarter of 2013, when: 91% of serotyped samples were ncHi, 6% were serotype a, e, or f, and 3% were Hib.
Age group was well reported (table). Of the laboratory reports during the second quarter of 2014: 83% were aged 15 years and over; 7% were under 1 year of age; and 6% were among 1 to 4 year olds and 3% were aged 5 to 14 years. The age distribution was similar to that in the second quarter of 2013, where: 80% were aged 15 years and over; 12% were under 1 year of age; and 4% were among both 1 to 4 year olds and 5 to 14 year olds. The overall increase in numbers in the second quarter of 2014, compared to the second quarter of 2013, was largely due to a 30% increase in cases in the 15+ age group (from 111 to 144); cases also increased in the 1 to 4 year age group, from 5 to 11 cases (an increase of 120%) whilst the case fell in infants under 1 year of age.
During this quarter 92% of cases in children under 15 years were ncHi (n=22/24). There was 1 case of Hib in this age-group; an infant, who was too young to have received the first dose of the DTaP/IPV/Hib vaccine, who presented with fever and made a full recovery. This was comparable to the second quarter of 2013 where 1 case in a child under 1 years old was confirmed.
1. Age distribution of laboratory-confirmed cases of Haemophilus influenzae by serotype, England and Wales, second quarter 2014 (and 2013)
Serotype | Age-group | Total, second quarter 2014(2013) | ||||
---|---|---|---|---|---|---|
<1y | 1-4y | 5-14y | 15+ | nk | ||
b | 1 (1) | – (–) | – (–) | 5 (3) | – (–) | 6 (4) |
nc | 9 (13) | 7 (4) | 6 (3) | 97 (87) | – (1) | 119 (108) |
a,e,f | 1 (–) | – (–) | – (2) | 16 (5) | – (–) | 17 (7) |
not typed | 1 (3) | 4 (1) | – (1) | 26 (16) | – (–) | 31 (21) |
Total | 12 (17) | 11 (5) | 6 (6) | 144 (111) | – (1) | 173 (140) |
Notes: “ –” Indicates that testing yielded no positives. Percentages may not add up to 100 due to rounding.