Research and analysis

HPR volume 9 issue 45: news (18 December)

Updated 29 December 2015

1. Laboratory confirmed pertussis in England: July-September 2015

In England there were 1322 laboratory confirmed cases of pertussis (culture, PCR, serology or oral fluid) reported to the Public Health England pertussis enhanced surveillance programme in the third quarter of 2015, from July to September 2015. Total cases were 21% higher than those reported in the same quarter of 2014 (1093 cases between July and September 2014).

The number of confirmed cases in infants under three months in the third quarter of 2015 (46 cases) was similar to the same quarter in 2014 (47 cases) and remains low. One infant with pertussis confirmed between July and September 2015 died. Of the 13 infants who have died following confirmed pertussis disease and who were born after the introduction of the maternal programme on 1 October 2012, 11 have been born to mothers who had not been immunised against pertussis during pregnancy.

Coverage of the whooping cough vaccine programme for pregnant women has increased in the third quarter of 2015 from 55.6% in June to 57.7% in September 2015 [1].

Total number of laboratory-confirmed pertussis cases per quarter in England, 2005 to 2015 (Q3)

Total case numbers of pertussis in all age groups greater than three months were higher in Q1-3 2015 (see figure) than the same quarters in 2014 with the greatest proportionate increase observed in infants aged 3-5 months and children aged 1-9 years. Overall activity remained higher in all age groups from one year and older relative to the pre-2012 peak and exceeded 2012 Q1-3 cases in the 5-9 year age group.

These raised levels of pertussis persisting in all age groups other than infants <3 months make it important that women continue to be encouraged to be immunised against pertussis during pregnancy (ideally between 28-32 weeks) in order to protect their babies from birth. The pertussis immunisation in pregnancy programme in England has shown high levels of protection against pertussis in babies born to vaccinated mothers [2,3].

For tabular material associated with this report, see the full PDF version.

1.1 References

1. Pertussis Vaccination Programme for Pregnant Women: vaccine coverage estimates in England, June to September 2015. HPR 9(42): infection report.

2. Amirthalingam G, Andrews N, Campbell H et al (2014). Effectiveness of maternal pertussis vaccination in England: an observational study, Lancet.

3. Dabrera G, Amirthalingam G, Andrews N et al (2014). A case-control study to estimate the effectiveness of maternal pertussis vaccination in protecting newborn infants in England and Wales, 2012–2013. Clin Infect Dis.

2. Group A streptococcal infections: first report on activity during the 2015 to 2016 season

Public Health England is continuing to monitor notifications of scarlet fever cases in England in the early phase of the 2015/16 season, following the high levels recorded last spring. According to the first report on Group A Streptococcus activity for the 2015/16 season [1], as of mid-December 2015, national scarlet fever activity is showing a typical seasonal pattern, gradually increasing from a low level of notifications each week, nevertheless elevated compared with previous years. Invasive disease reports are elevated for this point in the season although this might just reflect an earlier peak in seasonal activity than in recent years.

2.1 Reference

1. “Group A streptococcal infections: first report on activity during the 2015 to 2016 season” (see “Group A Streptococcus infections: activity during the 2015 to 2016 season”).

3. Mandatory HCAI reports quarterly trends: July to September 2015

PHE’s latest quarterly epidemiological commentary on trends in reports of Staphylococcus Aureus (MRSA and MSSA) and Escherichia Coli bacteraemia, and of Clostridium Difficile infections, mandatorily reported by NHS acute Trusts in England up to July-September 2015, has been published on the GOV.UK website [1].

The report includes tabular and graphical information and provides data for July to September 2015 quarter (updating the previous report published in September 2015). Some key facts are listed below.

3.1 MRSA bacteraemia

There has been a 13.3% decrease (1.7 to 1.5 reports per 100,000 population) in the rate of all reported MRSA bacteraemia between April-June 2012 and the current quarter (July-September 2015). This is part of an overall decreasing trend beginning from April 2007. However, more recently (July-September 2014 and July-September 2015) increases in both the counts and rates of total MRSA bacteraemia have been reported (from 182 to 200 and from 1.3 to 1.5 per 100,000 population, respectively). This has been observed in both Trust assigned counts and rates (from 69 to 78 reports and from 0.8 to 0.9 per 100,000 bed-days, respectively) and CCG assigned counts and rates (from 86 to 94 reports and from 0.6 to 0.7 per 100,000 population, respectively).

3.2 MSSA bacteraemia

The current quarter (July-September 2015) saw the highest rate of total MSSA bacteremia (19.2 reports per 100,000 population) since the mandatory reporting of MSSA bacteraemia cases was initiated in January 2011. The count of total MSSA bacteraemia has increased by 8.5% in the current quarter (July-September 2015, n=2,622) when compared to the same quarter in the previous year (July-September 2014, n=2,417). Similarly, in both the counts and rates of Trust apportioned MSSA bacteraemia reports, there has been a 4.2% increase from 674 to 702 reports and 7.9 to 8.2 per 100,000 bed-days, respectively, over the same time period.

3.3 E Coli bacteraemia

A 6.2% increase (from 69.2 to 73.5 reports per 100,000 population) has been observed in the rate of E. Coli bacteraemia when comparing the current quarter (July-September 2015) with the same quarter of the previous year (July-September 2014), with an overall increase of 21.1% in the rate of bacteraemia from 60.7 to 73.5 reports per 100,000 population since April-June 2012.

3.4 C. Difficile infection (CDI)

From July-September 2014 to July-September 2015 there was a slight increase (1%) in the counts and rates of total CDI reported from 3,971 to 4,009 reports and from 29.0 to 29.3 reports per 100,000 population, respectively. However within the same period, counts and rates of the Trust apportioned CDI reported have remained steady (from 1,353 to 1,355 reports, respectively, and 15.8 reports per 100,000 bed-days for both quarters).

3.5 Reference

1. PHE (10 December 2015). Quarterly Epidemiological Commentary: Mandatory MRSA, MSSA and E. coli bacteraemia, and C. difficile infection data (up to July-September 2015).

4. Increase in Salmonella Paratyphi B in England associated with travel to the Middle East

The PHE Salmonella Reference Service has identified a whole genome sequencing cluster of 10 cases of travel-associated enteric fever caused by infection with Salmonella Paratyphi B. Cases are geographically spread within England. Seven of the cases in this cluster are in UK residents who have returned from travelling to visit family in Kurdistan, northern Iraq; an additional two cases travelled to Turkey and one did not travel abroad. Within this cluster, two more closely related clusters containing three and five cases each have also been identified suggesting a common source. Between 2006 and 2014, only one case of Salmonella Paratyphi B associated with travel to Iraq has been reported so this cluster is unusual.

Seven cases travelled to Northern Iraq (n=5) and Turkey (n=2) during the English school holidays and symptom onset dates range from 5 to 29 August 2015 with travel occurring during July and August. A later family cluster of three cases had onset of symptoms in October and November after travelling to Northern Iraq in September and October.

On average, 1-3 cases of enteric fever associated with travel to Iraq or Turkey are reported in travellers from England, Wales and Northern Ireland each year and most of these have been caused by Salmonella Typhi, although in 2009, 15 cases were associated with travel to Turkey [1].

The Travel and Migrant Health Section (TMHS) within the National Infections Service are monitoring this situation and the health authorities in Iraq have been informed. Typhoid and paratyphoid (enteric fever) are subject to enhanced surveillance and all suspected cases of typhoid and paratyphoid should be investigated as per the Typhoid and paratyphoid: public health operational guidelines and reported to TMHS as soon as investigations are complete. Provisional data for enteric fever are published in the Health Protection Report on a quarterly basis.

Health advice for travellers to Iraq and other countries where typhoid or paratyphoid is a risk is available from the National Travel Health Network and Centre website.

Advice leaflets about typhoid and paratyphoid is available on the PHE webpages at: https://www.gov.uk/government/publications/typhoid-health-advice-for-travellers

Specific advice for those visiting friends and family abroad is also available from the PHE webpages: https://www.gov.uk/government/publications/travelling-overseas-to-visit-friends-and-relatives-health-advice.

4.1 References

1. HPA (2009). Enteric fever (Salmonella Typhi and Paratyphi) – 2009 update.

5. Avian influenza in France, November-December 2015

French authorities have reported 30 separate outbreaks of highly pathogenic avian influenza in France since 24 November 2015. The term “highly pathogenic” specifically refers to the illness the virus causes in birds rather than in humans. These outbreaks include:

• in Dordogne, 11 outbreaks were reported between 24 November and 15 December due to H5N1, H5N9 and H5N2
• in Landes, 13 outbreaks were reported between the 6 December, the 15 December, due to H5N9 and H5N2
• in Haute-Vienne, an outbreak of H5N1 was reported on 3 December
• in Gers, three outbreaks of HPAI H5 have been reported between 10 and 15 December, one due to H5N2, and two others awaiting full subtyping
• in the Pyrenees-Atlantiques two outbreaks were reported between 11 and 15 December, one due to H5N9 and one other awaiting full subtyping.

ANSES (the French Agency for Food, Environmental and Occupational Health and Safety) has confirmed that in the outbreaks, the identified strains are considered to be of European, rather than Asian lineage. It should also be noted that human infections have not been previously reported for H5N9 or H5N2 or for European origin H5N1.

The response to outbreaks of HPAI in Europe is governed by European legislation, and culling, cleaning and disinfection measures will be implemented. The risk of human infections would be limited to those directly involved in the culling and clean-up operations, however providing adequate PPE is worn then the risk is considered to be very low. The French authorities are actively following up the event. People exposed to infected birds are being monitored to immediately identify persons who develop influenza-like illness (ILI) or conjunctivitis, so that they can undergo further tests.

Defra is monitoring the situation closely in the UK and has published a risk assessment for the impact on the UK bird population.

PHE is also closely following the situation in relation to public health, although to date there have been no human cases of avian influenza reported by the French authorities. Well established national guidance for managing the public health response to avian influenza incidents is available [1].

5.1 Reference

1. PHE health protection collection: Avian influenza: guidance, data and analysis.