Transcript Influenza surveillance

North East Surveillance Sources
HPA – North East Regional Epidemiology Unit
09 April 2016
Why surveillance?
Disease surveillance;
“Ongoing scrutiny, generally using methods distinguished
by their practicability, uniformity and frequently their
rapidity, rather than by complete accuracy. Its main
purpose is to detect changes in trend or distribution in order
to initiate investigative or control measures.”
J.M. Last (1995) A Dictionary of Epidemiology
Outbreak identification
By assessing historical data, any exceedance in the
number of cases can be seen.
H1N1v
RSV
Influenza surveillance
HPA – North East Regional Epidemiology Unit
09 April 2016
Influenza – health burden
An acute viral disease of the respiratory tract.
Yearly seasonal influenza imposes a substantial health
burden on the population, both in the morbidity and the
mortality that it causes.
18,500-24,800 deaths each year in the UK1 are attributable
to seasonal influenza infections.
Over 90% of deaths occur among those aged 65 years and
older2.
1. Pitman et al., (2006) Assessing the burden of influenza and other respiratory infections in England and Wales. Journal of Infection. 54, 530-538
2. ed. Heymann (2008) Control of Communicable Diseases Manual
Surveillance Streams
The following are systems by which influenza information is
collected for the purposes of surveillance;
RCGP
QSurveillance
National
NPFS
Schools ILI Outbreak Surveillance
SRDS
RMN Flu Spotter
North East
Royal College of General
Practitioners
A network of 100 General Practices located throughout
England and Wales.
The total population covered by the WRS averages
approximately 900,000.
Practices submit consultation data for a number of
diseases, these are used to calculate consultation rates.
Also provides information on the number of cases with an
influenza-like illness who test positive for the pandemic
(H1N1) 2009 virus.
RCGP data
QSurveillance
Utilises a general practice computer system
A nationally representative sample of over 3000 practices
contributes the data.
Provides information on a population of approximately 20
million currently registered patients.
Data for a set of key disease indicators are presented in a
weekly bulletin.
Gives daily GP consultation rates.
Qsurveillance data
National Pandemic Flu
Service
Began on 23rd July 2009.
Issues antiviral drugs to people in England with an
influenza-like illness who call or log onto the internet site.
Provides data on the number of assessments and antiviral
collections through this service.
Gives a weekly rate (per 100,000) of antivirals collected
through NFPS.
NPFS data
National Schools ILI
Outbreak Surveillance
Based on reports from schools to local HPUs
Schools reported when absence rates exceeded 20% with
reports of influenza-like illness.
Initially, each region swabbed potential H1N1v cases at the
first three schools where the absence rate exceeded 20%.
The surveillance progressed in time to view a snapshot of
the number of schools affect in each HPU.
Seasonal Respiratory
Disease Surveillance
A North East initiative
Uses data from respiratory disease samples sent to three
laboratories in the region.
Shows the number of samples tested and the number
positive for a range of respiratory diseases.
Data presented by week over a year period, also shows
data from the previous year.
SRDS data
RMN Flu Spotter
Six participating GP practices in the North East (65
nationally)
Provides a weekly summary of samples sent to the HPA
lab for testing.
Shows the number of samples from these practices that
tested positive for Influenza.
Shows age, sex and region specific trends.
Other surveillance streams
Antiviral susceptibility tests – Respiratory Virus Unit, CfI
Hospitalisation data – number of hospitalisations with
confirmed pandemic influenza, voluntary.
Weekly (all-cause) death registrations – Office for National
Statistics
Sexual Health Surveillance
HPA – North East Regional Epidemiology Unit
09 April 2016
STI – health burden
The symptomless nature of many STI’s can result in;
• Serious complications in later years if left untreated
• An under representation of the scale of infection – knock on
effect to resource allocation
• A wider spread of infection – before diagnosis / difficulties
contacting previous sexual partners
Many infections are now common especially in young
people
Sexual Health Surveillance
Systems
• All sexually transmitted diseases
GUMCAD
e.g. gonorrhoea
• HIV
e.g. SOPHID
• Syphilis
Enhanced Surveillance
• Chlamydia
NCSP
• Antenatal screening
Screen for Infectious
diseases
Sexual health surveillance
Genitourinary Medicine Clinical Activity Dataset (GUMCAD)
Records all sexual health diagnoses from all GUM clinics
E.g. Chlamydia, Gonorrhoea, HIV and Syphilis diagnoses
Also collects age, gender and resident information
HIV surveillance
Unlinked Anonymous Prevalence Monitoring Programme
(UAPMP)
Monitors the prevalence of HIV infection in selected adult populations
Samples are irreversibly unlinked, anonymised and tested for HIV
infection
HIV New Diagnoses Database
Collects data on new HIV diagnoses, first AIDS diagnoses and deaths
in HIV infected individuals
Information is received from laboratories, GUM clinics and regional
reporting centres
HIV surveillance
Survey of Prevalent HIV Infections Diagnosed (SOPHID)
Individuals with diagnosed HIV infection who attend for HIV-related
care within the NHS
Drug Resistance Database
Systematic collation of HIV resistance data from HIV infected drugnaïve individuals
CD4 Count Database
Monitors national trends in immunosuppression among HIV-infected
adults by analysis of CD4 cell counts
Analysis of CD4 cell counts combined with other HIV surveillance
data provides information on late diagnoses, trends in
immunosuppression and the population effect of antiretroviral therapy
HIV surveillance
Syphilis surveillance
Enhanced surveillance
Records in depth information over and above normal surveillance e.g.
sexual habits
Collects resident and clinic information, sexual orientation and details
of contacts
Section of enhanced syphilis questionnaire
Where did the client meet their
sexual contacts?
Location
Pub/bar
Club
Sauna
Cruising area
Cottage
Dark room
Chatline
Internet
Other
Most
Some
None
Details of location(s)
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Syphilis surveillance
Chlamydia surveillance
National Chlamydia Screening Programme (NCSP)
Records the number of Chlamydia tests completed in the under 25’s
and percent positive
Antenatal screening
Screen for Infectious Diseases
Aggregate data collected during routine antenatal assessments
Includes number of tests booked and positive results for HIV, Syphilis
and Hepatitis B
Limitations of this system are;
• Out dated software
• No way of collecting disaggregate data
• Lack of detail