health protection

Health Protection has an important role to play in allowing us to keep healthy and stay on track. Just how much of a role can be seen when considering how, in recent years, we have seen new communicable diseases come to the fore. At the same time there has been a re-emergence of diseases that were previously thought to be controlled. All bring new challenges for Health Protection. For example:

This chapter describes some of the health protection issues in Lothian for 2006 and how we need to ensure we are getting and staying on track through responding to these challenges to protect the health of Lothian people.

Human Immunodeficiency Virus

Human Immunodeficiency Virus (HIV), the virus that causes Acquired Immunodeficiency Syndrome (AIDS), continues to be a major threat to public health throughout the world. Whilst Sub-Saharan Africa is bearing the brunt of the disease, HIV infection is a global pandemic with an estimated 4.1 million people becoming infected with HIV in 2005. Worldwide it is estimated that only a fifth of those who need the antiretroviral drugs that can slow the progression of HIV infection to AIDS have access to them.

In Lothian during 2005/06, there were:

In response to this, NHS Lothian is working in partnership to prevent and deal with HIV infection in MSM* and the African community living with HIV in Lothian. For example, a new health promotion campaign commenced in September 2006 to raise awareness of HIV among men who have sex with men, stressing the need for safe sex and HIV testing on a regular basis. NHS Lothian and partner organisations are working for better services for those from Sub-Saharan Africa living with HIV/AIDS resident in both Africa and Scotland. During 2005/2006 there were reciprocal visits of staff between Scotland and Zambia to provide training and project support.

* Men who have sex with men

Norovirus

Norovirus is a common cause of viral gastroenteritis that can spread rapidly from person to person via food or water, or by contact with an environment that has been contaminated by the virus. It is recognised that it can be a particular risk amongst large groups of people living in close proximity. Whilst the illness is usually mild it can be more severe among older people.

In recent years, outbreaks of illness due to Norovirus have been reported among passengers on cruise ships in various parts of the world. During the summer of 2006, the NHS Lothian health protection team, in partnership with Edinburgh City Council Environmental Health Department and others investigated and managed an outbreak of norovirus associated with a cruise ship. The ship made weekly voyages from Leith to destinations in the Baltic, and Iceland and Greenland over the summer months.

During a cruise at the beginning of June 2006, 124 out of 428 passengers and seven members of crew from the ship became unwell with symptoms of gastroenteritis. While public health measures to control the outbreak were instituted on the ship's return to Leith, further cases occurred among the passengers of the next two cruises (13 passengers and no crew members, and 109 passengers and five crew members respectively). Epidemiological investigations suggested norovirus infection, which was confirmed microbiologically.

With good cooperation from the cruise ship owners, officers and crew, a combination of public health measures were put in place to control the outbreak:

The prevention of norovirus is important and can be relatively straight-forward. Hand washing after going to the toilet and before eating or preparing food can help prevent the spread of infection. Travellers going on cruises can get further advice and information from the NHS Scotland fit-for-travel website: http://www.fitfortravel.scot.nhs.uk/

Case study

Outbreak of Cryptosporidium associated with a swimming pool

Cryptosporidium is a common source of gastrointestinal illness, usually associated with drinking water but also known to be associated with swimming pools. During November 2006, the NHS Lothian Health Protection Team, in partnership with Environmental Health Departments of two local authorities, Scottish Water and Health Protection Scotland investigated and managed an outbreak of cryptosporidiosis associated with a swimming pool.

Over a period of four days, three cases of cryptosporidium infection in children were reported to the Health Protection Team. Subsequent epidemiological investigations identified an additional three cases of cryptosporidiosis in family members of the initial cases. Enquiries regarding risk factors including exposure to farm animals, untreated water supplies, foreign travel, domestic pets and nursery or school attendance found no link between the cases. Apart from the drinking water supply, which had a satisfactory history on recent sampling, the one common exposure in all cases was swimming at the same pool on the same day.

The pool was closed pending investigation. Environmental and microbiological investigations of water treatment and water sampling were undertaken. Test results both for the mains water supply into the complex and the swimming pool were satisfactory and the pool was allowed to re-open three days later. The Outbreak Control Team made several recommendations regarding maintenance and filtration of the pool complex to be followed up by the local authority Environmental Health Department.

It was concluded that the most likely cause for the cases of cryptosporidiosis was an isolated faecal contamination event in the swimming pool on the day in question. Since the re-opening of the swimming pool, there have been no further related cases of cryptosporidium identified. All of the six cases in the outbreak made full recoveries.

The Health Protection Response

A combination of public health measures was required to investigate and manage this outbreak:

Key Messages

  • Cryptosporidium outbreaks can be associated with swimming pools. Good surveillance systems are required to identify potential links between cases at an early stage
  • Good communication and cooperation between agencies and the pool management facilitated the investigation and control of this outbreak

Old diseases, new public health threats

Measles and mumps - long considered under control due to the long standing immunisation programmes - have returned as a threat to public health. Whilst we often think of measles and mumps as childhood diseases, they can be serious illnesses and we often forget that measles remains a significant cause of mortality on a global basis.

Lothian is not free of this re-emerging risk. During 2006 a cluster of cases of measles involving four young children needed to be managed. Two of the cases were linked to a Lothian nursery and a further case was travel associated. Importantly, three of the cases were too young to have commenced MMR vaccination through the routine childhood schedule. Additional public health measures including offering public health advice to contacts of cases were required to control the cluster. However, as the protection of children too young to be immunised relies upon the achievement of adequate "herd immunity", a high uptake of MMR among the general population remains the key to preventing measles among these children.

At the same time there were further cases of mumps within Lothian in 2006, though at a lower level than in 2005 when a total of over 1500 mumps notifications were made. Outbreaks of mumps have occurred within two military establishments, one school and one university within Lothian over the last few years. All individuals identified as contacts of cases were given public health advice and a recommendation for MMR vaccination if they were not fully covered. All it takes is two doses of the MMR vaccine to provide full protection and to remember that it is never too late to protect children against measles mumps and rubella.

Syphilis is often thought of as a very rare disease. However, there has been an ongoing outbreak of syphilis in Edinburgh over recent years (see Figure 1). While the number of cases peaked at the end of 2004, sustained levels of infection are ongoing (see Figure). It is most prevalent among men who have sex with men, with 85% of infectious syphilis reported in the first six months of 2006 occurring in this at risk group reflecting the wider Scottish picture.

In Lothian, the health protection response includes:

Health protection is about surveillance, monitoring and managing outbreaks, and preventing communicable diseases from being passed on. This is one area where we simply need to do what we do well.