Research and analysis

HPR volume 9 issue 5: news (13 February)

Updated 29 December 2015

1. Ebola virus disease: international epidemiological summary (at 8 February 2015)

As of 8 February 2015, the World Health Organization reports a total of 22,894 clinically compatible cases (CCC) of Ebola virus disease (EVD), including 9,177 deaths, associated with the West African outbreak (see table). Provided case totals and, particularly, deaths are known to still under-represent the true impact of the outbreak in West Africa. While the majority of cases have been reported from Guinea, Liberia and Sierra Leone, cases have also been reported from Mali, Nigeria, Senegal, Spain, the United Kingdom (UK) and the United States of America (USA).

Substantial improvements in the epidemiological situation in Guinea, Liberia and Sierra Leone have been observed in the last 2 months. However, the complex nature of this outbreak means that control of EVD in West Africa continues to face significant challenges. In the last week, 144 new confirmed cases were reported from Guinea (65, 45%), Liberia (3, 2%) and Sierra Leone (76, 53%).

In Guinea, an increase in national incidence was reported for the third consecutive week. The geographical distribution of cases continues to vary and shift, with 8 prefectures reporting confirmed cases in the last week. While the majority of cases were reported from Forécariah, on the Sierra Leone border, Conakry the capital continues to record intense transmission. Reports of unsafe burials and incidents of community resistance remain an issue and may impede progress in EVD control.

In Liberia, reported case incidence remains at a low level with 3 confirmed cases reported in the last week, all cases were reported from Montserrado county. The situation in Liberia appears to be entering the final stages of control yet incidents of community resistance, EVD deaths in the community and unsafe burials continue to be reported. Careful monitoring of all cases and contacts is required to ensure all chains of transmission are stopped.

Sierra Leone continues to record the majority of new cases in the West African EVD outbreak. Currently, Port Loko, Freetown and Kambia are the worst affected districts. While there has been substantial improvement in national incidence in Sierra Leone in the last two months, the fluctuating trend in new cases in certain districts, as well as ongoing reports of community resistance and reports of unsafe burials, may impede control measures and eventual cessation of the outbreak.

The table below summarises Ebola virus disease international epidemiological information as at 8 February 2015.

Country Total CCCs Total deaths Current status
Guinea 3044 1995 Ongoing transmission
Liberia 8881 3826 Ongoing transmission
Sierra Leone 10,934 3341 Ongoing transmission
Mali 8 6 EVD free
Nigeria 20 8 EVD free
Senegal 1 0 EVD free
Spain 1 0 EVD free
UK 1 0 Single imported case
USA 4 1 Awaiting EVD free status
TOTAL 22,894 9177

Further information on the international epidemiological situation can be found in PHE’s weekly Ebola epidemiological update.

2. Group A streptococcal infections: update on seasonal activity, 2014/15

Public Health England is continuing to monitor notifications of scarlet fever in England following the substantial elevation in notifications reported last season (2013/14). The early part of the current season indicates continued elevated activity, with a steep increase being reported in the first few weeks of 2015.

According to the latest report on Group A Streptococcus activity for the 2014/15 season [1], as of end-January 2015, national scarlet fever activity is showing a typical seasonal pattern, gradually increasing from a low level of notifications each week. Most parts of England are reporting elevated levels of scarlet fever compared with previous years, including the exceptional levels of activity noted last year. National invasive disease rates remain within the norm for this time of year, although above average activity is being reported in some parts of the country.

The full report on Group A Streptococcus infections activity for the 2014/15 season is included in the PDF version of this issue of HPR.

2.1 Reference

  1. PHE (February 2015). Group A streptococcal infections: activity during the 2014 to 2015 season.

3. Wound botulism among people who inject drugs in Scotland and Norway

From 21 December 2014 to 9 February, there have been 15 probable or confirmed cases of wound botulism among people who inject drugs (PWID) reported in Scotland [1]. In the cases where information is available, all of the individuals had either obtained their heroin in, or sourced it via, Glasgow. Among the 6 that have been confirmed microbiologically, 3 are type B. Overall, a total of 21 people in Scotland have been admitted to hospital since 21 December 2014, with a severe illness where botulism has been suspected. Two of these 21 illnesses had other causes, and 4 remain under investigation [1].

There is also an ongoing cluster of cases in Norway. As of 10 February 2015, the Norwegian Institute of Public Health had reported 8 probable or confirmed cases of wound botulism in people who inject heroin in the Oslo area [2]. Prior to the present cases, 16 cases had been reported among PWID in Norway, including a cluster of 3 cases in 1997 [3] and 1 of 7 cases in 2013 [4].

It is currently not known if the current clusters of wound botulism among PWID in Scotland and Oslo are linked. The contamination of heroin with Clostridium Botulinum spores is thought to be an on-going and probably common occurrence, as the spores are widely found in the environment. These 2 clusters suggest that one-or-more batches of heroin with probably higher levels of spore contamination than usual are in circulation.

In the UK a total of 167 cases of wound botulism among PWID were reported between 2000 and 2013; no cases were reported before 2000 [5,6]. Prior to the current cluster in Scotland there had been a single sporadic case (laboratory confirmed, type B) in England, in 2014. So far this year, 2015, 1 case of wound botulism among PWID has been reported in England (laboratory confirmed, type B). Although investigations are ongoing, this case is currently being managed as a sporadic case with no links to the cases in Scotland or Norway. There have been no cases in Wales or Northern Ireland in recent years.

As C. Botulinum is an anaerobe, infection only occurs when the spores enter a suitable anaerobic environment, such as can be found in damaged tissues. In PWID such tissue damage can result from missed ‘hits’ (ie missing the vein when trying to inject intravenously) or when intentionally injecting intramuscularly or subcutaneously. In the UK, heroin is predominantly a brown powder that requires an acidifier for solubilisation. The acidic solution that results can increase the tissue damage at injection sites, particularly when injecting intramuscularly or subcutaneously. Most people who inject drugs do so intravenously and are unlikely to become infected when exposed to botulism spores because of the aerobic environment in the blood stream.

It is important that awareness of botulism infection among PWID is maintained, as promptly seeking healthcare can reduce the severity of the illness and prevent death. Updated materials on botulism for PWID, and those who work with them, have been produced and cascaded to appropriate services in England, and they are available from the Public Health England website [7]. Information on the management of suspected cases of wound botulism can also be found on the Public Health England website [8].

3.1 References

  1. Health Protection Scotland (10 February 2015). Botulism alert for people who inject drugs - update
  2. Folkehelseintituttet N (2015). Åtte tilfeller av botulisme hos injiserende rusmisbrukere i Oslo-området.
  3. Kuusi M, Hasseltvedt V, Aavitsland P (1999). Botulism in Norway. Euro Surveill. 4(1): 11-12.
  4. MacDonald E, Arnesen TM, Brantsaeter AB, Gerlyng P, Grepp M, Hansen BÅ, et al (2013). Outbreak of wound botulism in people who inject drugs, Norway, October to November 2013. Euro Surveill. 18(45): 20630.
  5. Wound botulism among PWID. Health Protection Report 7(43), 25 October 2013.
  6. PHE, Health Protection Scotland, Public Health Wales, and Public Health Agency Northern Ireland (November 2014). Shooting Up: Infections among people who inject drugs in the United Kingdom 2013.
  7. PHE website. Botulism: infection in people who inject drugs.
  8. PHE website. Botulism: clinical and public health management.