Memorandum by the Health Protection Agency
1. A recent report on Communicable Diseases
by the UK Department of Health stated that "post-war optimism
that their conquest was near has proved dramatically unfounded".
What is your assessment of the overall position? More specifically,
is it simply that not enough progress is being made in reducing
the spread of such diseases? Or is the global situation actually
deteriorating? Would it be an exaggeration to talk of a crisis?
1.1 It is clear that they have not been
"conquered". The introduction of effective vaccines,
antimicrobial therapy and improved sanitation over 100 years has
had a significant beneficial effect; while increasing levels of
international trade and travel, emergence of new infections (particularly
zoonotic infections), emergence of antimicrobial resistance, changes
in societal behaviour (eg sexual behaviour, uptake of vaccination,
urbanisation and the extension of human settlements into new ecological
settings), geopolitical factors, and war/strife with mass population
movement, have increased the risks of transmission and the impact
of these diseases. Some risks have never gone away, eg the risk
of pandemic influenza. The emergence of antimicrobial resistance,
and the potential lack of new antimicrobials, is probably the
greatest single "natural" threat, along with the emergence
of new infections and the threat of deliberate release.
2. What reliable data exist regarding
the numbers of people infected globally with the four diseases[1]
on which the Committee is focusing particular attention? What
trends are discernible in both the numbers infected and the patterns
of infection? And what are the main underlying causes of infection
and of any changes in its incidence and pattern?
2.1 WHO malaria figures are approximately 500
million cases, with at least one million deaths (approx 90% of
them in sub-Saharan Africa), per annum. There are around 1,750
imported malaria cases in the UK each year.
2.2 The WHO declared TB a global emergency
in 1991. The most recent assessment suggests that the epidemic
may be on the threshold of decline. Tuberculosis remains a major
cause of death with over 1.6 million deaths in 2005. The number
of new cases is still rising with about 8.8 million new cases
estimated to occur annually. This increase has been attributed
to the HIV pandemic, failures in TB control programmes, emergence
of drug resistant strains, poverty, conflicts and in certain countries
the dismantling of TB control infrastructure due to the perception
that it is a disease of the past. There are also significant funding
short-falls globally, and recent reports of the emergence of multi-drug
resistant TB.
2.3 Estimates of the total number of people
that have been infected with avian influenza H5N1 in humans are
made available by WHO. From 2003-07, 349 cases were reported with
216 deaths. Although the possibility of person to person spread
has been reported in a few incidents, the virus currently appears
to be very inefficient in transmission to and between humans.
2.4 The 2007 UNAIDS/WHO AIDS Epidemic Update
estimated that in the previous year 2.5 million became newly infected
and 2.1 million had died, and that there were 33 million people
living with HIV. It is also thought that the rate of increase
in the overall numbers living with HIV may be slowing as the numbers
of new infections has fallen, from an estimated peak of three
million annual infections in the late 1990s. In the UK estimated
numbers living with HIV is now 73,000, with up to a third remaining
undiagnosed. Much of the recent rise in HIV in the UK is due to
continuing migration of HIV-infected persons from sub-Saharan
Africa. Sexual behaviour together with the increasing complexity
of sexual networks in a globalised society continues to drive
HIV transmission.
3. What intergovernmental surveillance systems
exist to give early warning of outbreaks of infectious diseases?
Are these systems adequate? And what improvements might be made?
3.1 At a global level, formalised international
surveillance systems to give early warning of outbreaks of infectious
disease are largely managed or coordinated by the WHO (for some
parts of the World the WHO also provides the main focus for regional
surveillance). Within Europe, the recently established European
Centre for Disease Control and Prevention (ECDC) is increasingly
taking the lead in the operation and coordination of surveillance
that extends across national borders. The growing importance of
zoonoses as emerging infections, and the importance of internationally
distributed foodstuffs as vehicles of infection, mean that international
surveillance of animal infections, coordinated by the OIE[2],
and rapid international reporting of significant food contamination,
through the WHO Infosan[3]
network and the EU's RASFF[4]
system, also have an important role in the early warning of outbreaks
of infectious disease.
3.2 The implementation of the 2005 International
Health Regulations has formalised and enhanced the level of exchange
of early warning information between countries. The shift of coordination
of EU surveillance networks to ECDC has yet to demonstrate any
added value, and for some diseases there is concern that the capacity
for effective assessment and response to potential threats has
been diminished.
3.3 Beyond these European and global non-governmental
systems there are few formalised international surveillance systems.
EuroMed partners (non-EU countries surrounding the Mediterranean)
should be encouraged to actively support and strengthen their
participation in existing ongoing activities, such as EU networks
(eg Communicable diseases surveillance) and regional projects
(eg Episouth, Shipsan, Public Health Border Management) and consider
sustainable long term cooperation for the Region. There is one
system within the EU, RASBICHAT, that provides an early alerting
capability between member states. There is a similar system with
the GHSI (Global Health Security Initiative) of G7.
4. Given the continuance of current or planned
intergovernmental programmes to prevent or control the four diseases,
what predictions can be made of their likely spread and pattern
over the next 10 years?
4.1 For HIV there is a huge effort by UNAIDS
and by government to provide treatment, but surveillance of drug
resistance is poor. An increasing proportion of HIV cases in the
UK are migrants from high prevalence countries who acquire HIV
there. It is expected that an increasing proportion of such migrants
will be infected with resistant HIV. Increased survival will increase
transmission risk.
4.2 Although no increase in TB case numbers
was reported in the UK in the most recent year for which data
are available (2006), the underlying trend of the last two decades
remains one of increase. Future trends will depend on patterns
of immigration and the success of the tuberculosis control programme
outlines in the Chief Medical Officer's Action Plan.
4.3 No reliable prediction can be made about
the occurrence of either avian or pandemic influenza in future
years. History suggests that a new pandemic strain of influenza
virus is likely to emerge at some time and cause widespread human
illness. The extensive spread of the avian influenza H5N1 in wild
birds and poultry (despite control measures), and its ability
to cause severe disease in humans, has raised concerns about the
emergence of a new pandemic strain derived from the current H5N1
virus.
4.4 The global malaria situation will remain
very serious for at least the next 10 years. Eradication is extremely
unlikely at present. The extent to which malaria is controlled
will depend on the success of current programmes to roll out insecticide-treated
bed nets and artemisinin combination therapy, supported by parasite-based
diagnosis.
5. What do you consider to be the principal
blockages to achieving progress in the prevention or control of
the four diseases? And how might these blockages be removed by
more, or better-targeted or better-coordinated intergovernmental
action?
5.1 Sharing experience, knowledge and expertise
is a key component in global efforts to prevent and control the
four diseases. The UK has considerable technical expertise in
a range of scientific aspects of disease control and prevention,
and the potential to contribute substantially to this. TB is used
here to illustrate the issues posed.
5.2 Trends are determined by factors outside
the UK and control measures must include interventions applied
globally. This might be helped by better coordination of UK funded
TB work carried out in the UK and overseas. Consideration should
be given to the funding of an international group/section whose
remit is primarily to work overseas in countries with a high incidence
of TB, and/or drug resistant TB with the aim of supporting their
national TB control efforts i.e assist in solving the problem
at source. Such a group exists within the USA Centers for Disease
Control (CDC). The USA supported the Mexico TB programme through
the CDC, and was cost effective. This approach would work best
with direct co-operation between DH and DFID and agencies such
as the HPA.
5.3 Emergence of drug resistant strains
including those resistant to virtually all effective anti tuberculosis
drugs is a serious problem. More rapid identification of drug
resistance is now possible for many drugs but further research
is needed to develop better diagnostic systems for many second
line drugs and for new agents. Better co-ordination to plan and
implement phase 1, 2 and 3 clinical trials of new drugs is needed
across the EU and in countries where the need is greatest but
which have the poorest resources. Improved joint co-ordination
and implementation between DH and DFID and UK agencies could assist
in this regard as current activity is largely left to USA organisations.
Despite considerable funding to the WHO the UK has relatively
little influence on the direction of WHO activity compared to
other countries who frequently contribute less but take an active
role in influencing global policy.
5.4 Lack of a new drug (since the 1970s)
or a vaccine (since BCG, which is not particularly effective).
A number of new candidate drugs and vaccines are currently being
developed. Further funding of this work will help in which UK
expertise and funding is joined to current international activity
funded through the Gates or Global Fund or Wellcome Trust.
5.5 Poor markers of cure in drug resistant
TB patients eg, although guidelines exist, in practice it is a
long and uncertain process to determine when such a patient is
truly non-infectious and cured.
6. What role does your organisation play in
combating the four diseases? Do you believe that it is correctly
configured and adequately resourced to do the job? With which
other organisations do you collaborate? How would you assess the
degree of synergy?
6.1 The HPA's role in combating communicable
disease in general includes: infectious disease surveillance;
providing specialist and reference microbiology and microbial
epidemiology services; co-ordinating the investigation and response
to outbreaks and other communicable disease threats and incidents;
providing evidence-based expert advice and guidance to government,
health professionals and others with a responsibility for the
control and prevention of infectious disease, and to the public,
undertaking research, teaching and training; and providing the
national focal point and competent body functions for the UK in
meeting international obligations and coordinating international
collaborations in communicable disease control and prevention.
The continuing emergence of new or re-emergent infectious disease
and growing expectations on the protection of health at the individual
and population level are putting significant strains on the Agency.
6.2 Key partners in the work of the Agency
in combating infectious diseases are the NHS, Local Authorities,
Department of Health, the Food Standards Agency, DEFRA and the
VLA, and international bodies such as the WHO, the EU and ECDC.
The degree of synergy varies.
6.3 Funding to enable the HPA to engage
more in international work to track infections that threaten our
population is needed. This issue was addressed by a previous Lords
Committee (The House of Lords Science and Technology Committee,
4th Report of 2005-06 session on Pandemic Influenza published
16 December 2005. http://www.parliament.uk/hlscience/
). To quote: The Government should also make every effort to ensure
that the efforts of United Kingdom departments and agencies in
both animal and human health are fully co-ordinated. We therefore
recommend that the Government review the current rules governing
funding of HPA activities overseas.
7. What are the main non-health causes (eg
global warming, poverty, changes in land use, international travel,
lifestyle, population) of the spread of the four diseases? To
what extent can intergovernmental action in non-health fields
contribute to alleviation of their spread? What action is taking
place or planned in these areas? And what more needs to be done?
Do you consider that there is sufficient "joined-up"
thinking in approaching the problem?
7.1 Poverty, international migration, conflict
leading to dispersal and displacement of populations, increased
ease and rapidity of travel and behavioural changes (see also
1.1) all contribute to spread. Alleviation of poverty attacks
the route cause of TB and malaria. Successful TB control can be
achieved through TB programmes such as those operated in some
parts of Africa and Asia, but co-infection with HIV compromises
these efforts. Better integration of TB and HIV control measures
will assist in the control of both diseases. Laboratory support
for diagnosis is identified currently as a major weakness, and
increasing funding to the sustainable development of new laboratory
facilities globally is important.
7.2 For AIDS in particular there is a need
to further address social drivers, notably the low status of women,
homophobia, stigma and inequalities.
7.3 Avian influenza is primarily a zoonosis
spread by birds. The two main routes of spread are migration and
commercial poultry operations; smuggling of wild birds also presents
a potential route. Improved surveillance and the sharing of these
data amongst countries would enable better preparedness and response.
Improving compliance with regulations relating to animal husbandry
to identify diseases early and the registration and accurate transit
documentation of farm animals would enable potential sources and
routes of infection to be identified.
8. Cases of Tuberculosis fell progressively
in the UK until the mid-1980s but started to rise again in the
early 1990s. Around 6,500 cases are now reported each year, an
increase of about a quarter since the early 1990s. What are the
main factors of the revival of Tuberculosis infections in Britain?
And how could intergovernmental action help to reverse the trend?
8.1 The annual number of TB cases reported
in the UK now exceeds 8,000 (8497 in 2006). The main factors responsible
for its re-emergence TB are immigration from high incidence countries
and the rise in HIV infection. Other factors include ongoing outbreaks
in population sub-groups such as the homeless, injecting drug
users and prisoners. Although travel to high incidence areas,
poverty, poor housing and health infrastructure on UK trends is
likely to be small, enlargement of the EU encompassing countries
with a high TB incidence or high rates of drug resistance poses
new risks. A greater integration of social and health services
to create a "one-stop approach" in which residency,
accommodation and health issues can be addressed simultaneously
is needed.
9. Tuberculosis is potentially curable by
long-term antimicrobial therapies. Yet the numbers of reported
cases worldwide seem to be rising. Are the necessary medicines
not getting through to patients? What are the barriers to effective
long-term therapy? Are we now seeing infections which stem from
other conditions—eg HIV/AIDS? Or are there other reasons
why a treatable disease should be spreading? How might intergovernmental
action help to deal with this situation?
9.1 The global rise in cases of tuberculosis
is primarily related to the HIV pandemic, especially in sub Saharan
Africa. Other factors such as poverty, lack of or breakdown in
health care services/infrastructure, conflicts and migration have
played an important role. The most recent global assessment of
the WHO's Directly Observed Therapy—Short Course (DOTS)
strategy for tuberculosis suggests progress is being made worldwide.
Diagnostic and treatment facilities are, however, lacking in many
parts of the world. This is especially the case for drug resistant
forms of tuberculosis. A short fall of $1.1 billion in funding
was estimated for 2007. Global diagnosis of TB remains seriously
short of international targets; such delays permit a greater spread
of infection and in the case of drug resistant TB leads to a higher
mortality particularly in individuals co-infected with HIV. Improvements
in laboratory diagnosis and treatment facilities are required.
10. To what extent do you believe that the
2004 Stockholm Convention limiting the use of DDT against Malaria-carrying
mosquitoes has been a factor of increases in the spread of the
disease? Has any risk analysis been carried out comparing the
relative dangers to human health posed by DDT and Malaria?
10.1 In the pre-amble to the Stockholm Convention
on Persistent Organic Pollutants, there is mention of the desirability
of replacing DDT house spraying against malaria mosquitoes by
equally effective and affordable alternatives, if and when these
become available. However, there is a detailed amendment in the
Convention which specifically authorises continued indoor use
of DDT against disease vectors using WHO approved methods. The
amendment accepts that outdoor use of DDT against agricultural
pests should be banned because of the evidence that DDT harms
wildlife. There is evidence that lack of use of DDT contributes
to increases in infection.
10.2 After 50 years of successful use of
DDT in South Africa from 1945 to 1995 they switched to pyrethroid
spraying. Within four years, one of the two important malaria
transmitting species in southern Africa, Anopheles funestus, evolved
resistance to pyrethroids, and incidence of malaria cases increased
four-fold. Switching back to DDT spraying in 2001, and adopting
Artemisinin Combination Therapy as first line anti-malaria drug
in 2002 led to a 91% decline by 2004 (Maharaj et al, 2005, S.Af
Med J 95: 871-4). With South African assistance parts of Zambia
and Mozambique have successfully taken up indoor spraying with
DDT.
10.3 There have been numerous published
reviews of the evidence about possible adverse effects of DDT
on human health. Most show no convincing evidence of such adverse
effects. A long term detailed study in Guyana showed the beneficial
effect of DDT on maternal and infant survival and on live birth
rate over three decades (Giglioli 1972 Bull WHO 46: 181-202).
The implications are that the beneficial effect of DDT used to
eradicate malaria far outweighs any adverse effects.
11. What intergovernmental action is planned
or in hand for early detection of the transmission of Avian Flu
from birds to humans and of human-to-human transmission in potential
source countries? Is this proving sufficiently effective to prevent
an Influenza pandemic? What more could be done?
11.1 WHO is the principal coordinator of
global intergovernmental action in relation to the human aspects
of avian influenza; the OIE coordinates the animal aspects of
avian influenza. WHO, in addition to coordinating action with
OIE, has taken action in three areas; surveillance, investigation
and management of incidents and international control measures.
The WHO Global Influenza Surveillance Network, comprising four
collaborating centres and 121 institutions in 93 countries, established
to collect data on circulating strains of influenza to inform
the composition of influenza vaccine each year, now serves as
a global alert mechanism for the emergence of influenza viruses
with pandemic potential eg, the current avian influenza H5N1.
11.2 International investigation and support
to avian influenza incidents affecting humans is channelled through
the WHO Global Outbreak Alert and Response Network (GOARN) established
in 2002.
11.3 The 2005 revision of the International
Health Regulations (IHRs) includes specific provisions for reporting
and response to public health threats, including avian influenza.
In June 2007, the HPA became the National IHR Focal Point for
alerting the WHO of UK incidents of international significance.
In addition to WHO, the ECDC, is increasingly becoming a focus
for the coordination of action on avian influenza in Europe. The
Global Health Security Action Group (GHSAG) of the G8 countries,
of which the UK is a member, is also committed to coordinating
intergovernmental action on pandemic and avian influenza in the
G8 countries and is currently identifying research gaps with a
view to developing a combined and coordinated research effort
in this area.
11.4 Strengthening and supporting the analytical
and epidemiological capability of the HPA contribution to WHO
and ECDC could improve further the exchange of information and
contribution that the UK can make to effective intergovernmental
working.
12. To what extent do you consider that the
rise in infections in the four diseases is attributable to increased
microbial resistance to antibiotics? What intergovernmental action
is taking place in this area?
12.1 Between 5 and 10% of cases of tuberculosis
worldwide are caused by drug resistant strains. Increases in the
numbers of drug resistant cases are being seen, including increases
in multi-drug resistant cases. The current global cost of treating
cases with resistant strains exceeds that for all the remaining
cases combined. Poorer countries with a significant case load
have insufficient resources to effectively provide care for these
patients. Such patients have a high mortality particularly if
co-infected with HIV.
12.2 Plasmodium falciparum, which now accounts
for over 75% of the malaria cases seen in the UK is the most pathogenic
species of malaria parasite and, if untreated, can give rise to
potentially fatal cerebral malaria and other severe and complicated
forms of malaria. It has become resistant to chloroquine (CQ)
in all but a few malarial areas. Resistance to antifolate drugs
has been reported in Africa, and to those and many other drugs
in SE Asia, including worrying early reports of possible emerging
resistance to the new artemisinin based drugs. Resistance to CQ
is also now reported in Plasmodium vivax.
12.3 Intergovernmental action against malaria
(including drug-resistance) includes the WHO Global Malaria Programme
(previously "Roll Back Malaria"), the Global fund to
Fight AIDS TB and Malaria (set up by G8 in 2001) and the Medicines
for Malaria Venture (MMV) which receives funding from a variety
of international sources, including Dfid.
13. In a number of countries, including the
UK, there is a problem with hospital-acquired infections. What
intergovernmental sharing of knowledge is taking place to help
bring this problem under control?
13.1 There is a lack of a co-ordinated information
sharing system directly between governments on healthcare associated
infections. This will become increasingly important as healthcare
provision within the EU becomes a common market. There are a number
of significant barriers such as which infections are counted (including
the definitions used for infection types and the different ways
in which rates of infection are calculated), and the differing
levels of mandatory reporting between countries. The differences
between healthcare systems (eg state, insurance based, private)
also complicate matters.
13.2 Most European counties submit data
to the EARSS (the European Antimicrobial Resistance Surveillance
System); this provides useful comparative data between countries
on the extent of antibiotic resistance in bacterial pathogens
associated with healthcare associated infections. This information
is distinct from the rates of different types of healthcare associated
infections.
14. Are there any difficulties with regard
to patents or intellectual property which are impeding the flow
of medicines or other control methods to those infected? Is intergovernmental
action needed to improve the situation?
14.1 Intellectual property and effective
patents are an essential mechanism in providing an incentive for
companies to invest in new anti-infective drugs and vaccines,
and indeed there is some evidence that the current period of patent
protection may not be sufficiently long to make drug development
attractive to investors. Certain pressure groups and governments
of lower income countries have taken the view that patents inherently
impede the flow of cost-effective medicines to those infected.
This has proved particularly controversial over the past decade
in the case of HIV drugs, resulting in a series of compromises
in which pharmaceutical companies have drastically reduced prices
in lower income countries. In the case of fast-moving scientific
areas such as pandemic influenza vaccines, patents covering "enabling"
technologies could hinder development if not effectively developed
or licensed to others by the owner and, on rare occasions, this
might give rise to a case for compulsory licensing. This is an
area that might usefully be kept under review by an intergovernmental
forum.
14.2 It would be inappropriate to tackle
individual isolated problems by introducing general intergovernmental
measures that may well be counterproductive. There may be scope,
however, for agreement on "best practice" to underpin
a responsible global approach to the development and use of intellectual
property. This might include, for example, discouraging attempts
to patent the sequences of newly emerging viruses or virus strains
in a way that restricts the development of counter measures, or
encouraging public sector organisations to adopt patent licensing
strategies that ensure competition and that favour developing
countries.
15. What interchange exists between States
in regard to knowledge of and training in the diagnosis and treatment
of the four diseases or regarding preparations for dealing with
outbreaks? What improvements might be made through intergovernmental
action?
15.1 Intergovernmental knowledge and training
is largely facilitated by the WHO. Furthermore, within Europe,
the ECDC co-ordinates activities which support the exchange of
knowledge between member states. For TB, informal networks such
as the International Union against Tuberculosis and Lung Disease
and its European branch and the European Respiratory Society all
contribute to the exchange of knowledge and training.
16. The International Health Regulations 2005
are intended to provide a global framework for the rapid identification
and containment of public health emergencies. How effective do
you consider this response system to be? Do improvements need
to be made?
16.1 The new reporting arrangements under
the 2005 IHR have been in operation since June 2007. The system
appears to provide a more sensitive and focussed mechanism for
alerting WHO and member states to potential threats than previous
systems operated by the WHO. There is, however, room for improvement,
both in the speed with which WHO undertakes its risk assessment
of reported incidents, and in the mechanisms used for alerting
countries to potential public health events of international concern
(PHEICs). Improvements are also needed on harmonisation of quality
of risk assessment to inform whether IHR reporting is warranted,
and if warranted, to better inform recipients of the alert.
17. What intergovernmental planning has been
undertaken to cope with the impact of an outbreak of infectious
disease caused by deliberate release of micro-organisms into the
environment? Is there adequate liaison between the various agencies
involved, including intelligence, law enforcement and health care
professionals? How could action by intergovernmental bodies help
further?
17.1 The intergovernmental planning to reduce
the impact of an outbreak of infectious disease caused by the
deliberate release of microoganisms into the environment has taken
place through initiatives led by the Health Security Committee
of the European Commission (ECDC is a member), and through initiatives
led by the GHSI of G7 (of which WHO is a member).
17.2 There has been adequate and indeed
very good liaison between the agencies involved including intelligence,
law enforcement and the Health Protection Agency in the UK. Intergovernmental
actions include the UK hosting a forensic epidemiology workshop
for G8 member states and the design of a training course for the
EU. The WHO has also been active in this field and published a
response manual. The UK has an excellent record in using exercise
scenarios to test and improve plans. The EU has commissioned the
UK to provide exercises. Future action by intergovernmental bodies
should build on this UK experience by utilising the exercises
in many more countries.
17.3 The threat of smallpox has been reduced
by the actions of WHO and intergovernmental initiatives in the
Global Health Security Initiative (GHSI) of G7 through measures
to improve recognition and response and stockpiling of vaccine.
18. Though our remit is focused specifically
on known infectious diseases, we would be interested to know how
you view the global threat from new or previously unrecognised
ones and from the transmission of infections from animals to humans
18.1 All of the issues raised under Q1 are
also factors here (see also New and Emerging Infections—the
Threat to Europe. Borriello, P Eurohealth 11:7-8). Roughly one
new disease emerges each year, nearly all from contact with animals.
Some of these have the capacity to form global epidemics (HIV),
others cause locally significant outbreaks of disease with human
and economic consequences (Nipah).
19. What resources (subscriptions, staff,
training, medicines etc) does the UK Government commit to intergovernmental
bodies to help in the fight against the four diseases listed?
No response.
20. Do you wish to provide any other relevant
information in addition to what you have said in answer to the
above?
No.
January 2008
1 HIV/AIDS, Tuberculosis, Malaria and Avian Influenza. Back
2
OIE-Word Organisation for Animal Health Back
3
WHO specified the International Food Safety Authorities Network
(INFOSAN) in 2004 Back
4
The Rapid Alert System for Food and Feed (RASFF) is a system which
has been in place since 1979 Back
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