Meningitis January Dr Andrew Lee Consultant in Communicable Disease Control, PHE Information in this slide set was correct as of 21.1.

Transcription

1 Meningitis January 2016 Dr Andrew Lee Consultant in Communicable Disease Control, PHE Information in this slide set was correct as of

2 Outline What is meningitis What causes it What are the signs and symptoms How common is it? How infectious is it? How to prevent infections? How good is vaccination?

3 What is meningitis? Meningitis describes inflammation of the meninges i.e. the tissue that covers the brain and spinal cord.

4 What are the causes? There are many different causes of meningitis: - Bacterial infections - Infections with viruses and other micro-organisms - Medications e.g. antibiotics, some epilepsy medication - Cancers e.g. melanoma, lung cancer, breast cancer - Autoimmune conditions like Systemic Lupus Erythematosus (SLE)

5 What are the signs and symptoms?

6 What are the signs and symptoms? When an infection is found in the circulating blood this is called septicaemia, a.k.a. blood poisoning This may lead to: Rash Severe aches and pains in muscles Cold hands and feet Rigors Abdominal cramps

7 The Glass Test Spots do not blanch on pressure.

8 How common is Neisseria meningitidis Found naturally in the throat or nose and will only occasionally cause disease ~ 10% of the population will carry N. meningitidis Highest carriage (~25%) in year olds Not known why some people carry the bacteria without harm while others develop disease The risk of getting the disease is very low. Although meningococcal disease is infectious and can cause outbreaks, 97 out of every 100 cases are isolated, with no link to any other cases. Meningitis Research Foundation

9 How common is the infection? 2 to 6 per 100,000 cases of infection each year Most of the infections occur in children <5 years of age Peak incidence in under 1s. Smaller secondary peak in young adults (age years) Most cases occur sporadically, less than 5% of cases occur in clusters Outbreaks may be more common among teenagers and young adults (e.g. in schools and universities). Marked seasonal variation with peak in winter.

10 Laboratory confirmed cases Laboratory confirmed cases of invasive meningococcal disease in England, epidemiological years 2005/ /15* / / / / / / / / / /2015 Epidemiological years (July-June) *2014/15 data is provisional Date source: PHE Meningococcal Reference Unit. Surveillance by PHE Immunisation Department Last Update August 2015 Please see link for more information and data

11 Laboratory confirmed cases Laboratory confirmed cases of invasive meningococcal disease in England, by age group, epidemiological years 2005/ /15* B C W135 Y Other < >=65 Age group (years) *2014/15 data is provisional Date source: PHE Meningococcal Reference Unit. Surveillance by PHE Immunisation Department Last Update August 2015 Please see link for more information and data

12 The infection is more prevalent in some areas of the world Red meningitis belt Orange epidemic zone Grey - sporadic

13 How infectious is it? Infection is not easily spread Transmitted from person to person by inhaling respiratory secretions from the mouth and throat or by direct contact (kissing) Close prolonged contact is usually required The germ does not live long outside the body

14 What is the risk Based on data from England and Wales, the risk of another case occurring after the initial case is: 1 in 300 for persons in the same household 1 in 1,500 in a preschool 1 in 18,000 in a primary school 1 in 33,000 in a secondary school (Compared to risk of dying in a road accident: 1 in 18,000 p.a.) In most clusters, secondary cases occurred within one week of the index case and by the end of the third week the risk of a secondary case was similar to baseline.

15 No. of deaths How severe is it? Death rates from the disease are around 5-10% Year

16 Who is at highest risk? A contact for meningitis is taken to be any person who has had close contact with a case in the past 7 days Close contact is defined as follows: - kissing, - sleeping with, - spending the night together or - spending in excess of 8 hours in the same room

17 Neisseria meningitidis Several distinct types (serogroups) exist. The most common pathogenic serogroups are groups B, C, A, Y and W135. Most disease in the UK is caused by serogroups B (59%) and C (36%). Significantly fewer cases caused by serogroup C since routine vaccination introduced

18 Preventing further infections We try to identify all close contacts as they are the ones at highest risk. The close contacts identified may be offered antibiotics. This is to clear possible carriage of the germ and reduce the likelihood of spread.

19 Immunisation No vaccine is ever 100% effective Men C vaccine ~88-96%, Men B vaccine ~93% Vaccines take time to work Vaccines only work against a specific strain of the germ - If the serotype of meningococcus is vaccine preventable, vaccination may be offered to unprotected contacts Vaccine protection does not always last forever That said, vaccines still offer the best chance of protection.

20 What the experts conclude about vaccination after a case Meningitis B vaccine is unlikely to afford adequate protection rapidly enough after a single dose (especially for young children who are at highest risk) and the vast majority of secondary cases occur within a few days after disease onset in the index case. Realistically, however, vaccine response is likely to take at least 14 days from administration of the first dose to offer any protection.

21 Routine childhood immunisations: Men C immunisations since Men B vaccine rolled out 2015 for children < 1 year

22 Routine adolescent immunisations: Men C vaccination programme since about 1999 for Y9s. Introduction of Men ACWY programme in autumn 2015 to replace Men C. Also, priority group were the Y13 students who had just left school/freshers at uni A two year catch up programme of Y11 students is planned to commence in early 2015, so this will catch up current Y11 students this academic year and current Y10 students next academic year. There will also be a further catch up programme for the current Y13 students.

23 Where to get more information NHS Choices website: Patient.info website: Meningitis Research Foundation: Meningitis Now Tackling high blood pressure