Transcript α2-3
熊本県獣医療職員研修会 越境性動物疾病（TAD）の現状 鹿児島大学農学部越境性動物疾病（TAD）研究センター教授 獣医学科病態予防獣医学講座獣医公衆衛生学分野 岡本嘉六 Approximately 75% of recently emerging infectious diseases affecting humans are diseases of animal origin; approximately 60% of all human pathogens are zoonotic. Quoted from CDC, USA Examples of emerging infectious disease (Pathogen, Year, Natural reservoir) BSE 1986/1993 Cow SARS 2003 palm civet et.al HPAI H5N1 1997/2003 Water bird HPS 1993 Rodentia HPS: Hantavirus Pulmonary Syndrome SARS: Severe Acute Respiratory Syndrome West Nile 1999 Bird/Mosquito Ebola 1976 Monkey H1N1 Pandemic 2009 Swine/Bird Lassa 1969 Rodentia Nipah virus 1998 Megabat/Swine E. Coli O157 1982 Cow/Food Hendra virus 1994 Megabat/Horse VzHF 1991 Rodentia BzHF 1994 Rodentia Venezuelan & Brazilian Hemorrhagic Fever Direct zoonoses an vertebrate host Avian influenza, Rabies, Hantavirus, Psittacosis, Bovine tuberculosis, Brucellosis, E. coli O157, Anthrax Cyclozoonosis more than one vertebrate host Echinococcosis, Cｙｓｔｉｃｅｒｃｏｓｉｓ, Toxoplasmosis, Tｒｉｃｈｉｎｉａｓｉｓ Saprozoonoses Metazoonoses an invertebrate host West Nile fever, Yｅｌｌｏｗ ｆｅｖｅｒ, Ｒｉｆｔ Ｖａｌｌｅｙ ｆｅｖｅｒ, Plague, Aｎｉｓａｋｉａｓｉｓ non-animal reservoir Tetanus, Bｏｔｕｌｉｓｍ, Aｓｐｅｒｇｉｌｌｏｓｉｓ, Hｉｓｔｏｐｌａｓｍｏｓｉｓ, Tｏｘｏｃａｒｉａｓｉｓ, Fascioliasis, Anthrax Global Framework for Transboundary Animal Diseases (GF-TADs) May 2004 Transboundary Animal Diseases(TADs) may be defined as those epidemic diseases which are highly contagious or transmissible and have the potential for very rapid spread, irrespective of national borders, causing serious socioeconomic and possibly public health consequences. The GF-TADs is a joint initiative of FAO and OIE which combines the strengths of both organisations in the fight against TADs world wide. It is composed of a global component at the OIE and FAO Headquarters level and of regional and sub-regional components. The ultimate aim of the Programme is to control and eradicate the most significant animal diseases including those transmissible to humans. The GF-TADs programme will be developed along four main thrusts: (1) A regionally led mechanism, to operationally address and implement action against priority diseases as agreed by relevant stakeholders; (2) The development of Regional and Global Early Warning Systems for major animal diseases; (3) The enabling and application of research on TADs causing agents at the molecular and ecological levels for more effective strategic disease management and control; and, (4) The completion of the Global Rinderpest Eradication Programme set for achieving global declaration of freedom by the year 2010. Contributing to One World, One Health A Strategic Framework for Reducing Risks of Infectious Diseases at the Animal-HumanEcosystems Interface 14 October 2008 Contents 1. Introduction: HPAI and beyond 2. Achievements and lessons learned from HPAI and their relevance to Emerging infectious diseases(EID) 3. Emerging and existing infectious diseases and their impacts 4. The Strategic Framework 5. Specific objectives and outputs 6. Cross-cutting issues to be addressed This principle may 7. Institutional issues be called “OWOH” 8. Financing the framework or “One Health”. Executive summary Humanity faces many challenges that require global solutions. One of these challenges is the spread of infectious diseases that emerge (or re-emerge) from the interfaces between animals and humans and the ecosystems in which they live. This is a result of several trends, including the exponential growth in human and livestock populations, rapid urbanization, rapidly changing farming systems, closer integration between livestock and wildlife, forest encroachment, changes in ecosystems and globalization of trade in animal and animal products. OWOH Reclamation Forest with wildlife Human living area Various pathogens existing among the wildlife could infect livestock and people. OIE/FAO Network of Expertise on Animal Influenza(OFFLU) Animal influenzas threaten animal health and welfare, agricultural productivity, food security, and the livelihoods of farmers in some of the world’s poorest countries. Both H5N1 HPAI and pandemic H1N1 2009 have also highlighted the potential for animal origin influenza viruses to evolve into global public health threats. To ensure that the impact and risks for animals and humans are kept at a minimum, it is vital that the animal health sector takes the lead in monitoring influenzas in animals and in sharing this information with the international community. Waterbird posess all typs of H, but other Waterbird (Anatidae) H1～H16 (α2-3) α2-3 animals infect with difinitive types. On rare occasions, surpass the “species barrier” Swine α2-3、α2-6 Poultry α2-3 Horse α2-3 H1、H3 (α2-3、α2-6) H5、H7 (α2-3) H3、H7 (α2-3) H5N1 Human α2-6 α2-6、α2-3 α2-3 receptor localized on alveolar cell H1、H2、H3 (α2-6) The flu usually prevalent only within the same species. Animal αreceptor H type of virus (Affinity to αreceptor) Shape and thickness of arrows show the frequency of infection. FAO EMPRES PB2 PB1 PA HA NP NA MP NS Emergence of pandemic H1N1 2009 Human H3N2 Swine H1N1 Double H3N2 97-98 × Triple H3N2 Poultry H?N? 98 × ⇒ ⇒ × In North America, regional virus repeatedly infect mutually between man and pig. Eurasia Swine H1N1 Swine H1N1 Triple H1N2 2000 - 09 ⇒ PB2 PB1 PA HA NP NA MP NS Triple H1N1 × ⇒ Pandemic H1N1 2009 Novel H1N1 Confirmed and Probable Case Rate in the United States, By Age Group Novel H1N1 U.S. Deaths, By Age Group From April 15 to July 24 2009, USA reported 43,771 confirmed and probable cases of novel influenza A (H1N1) infection. Of these cases, 5,011 people were hospitalized and 302 people died. The information analyzed by CDC supports the conclusion that novel H1N1 flu has caused greater disease burden on people younger than 25 years of age than older people. High incidence of young generation and significantly higher fatality rate than seasonal influenza strengthened vigilance worldwide. 2009 H1N1 Early Outbreak and Characteristics Percentage of Visits for Influenza-like Illness Reported by the U.S. Surveillance Network FluView USA the national baseline Number of InfluenzaAssociated Pediatric Deaths by Week of Death On April 28, WHO pulled up flu alert level from "3" to "4", and to "5" on the next day, declaring “Pandemic” on Jun 12. People afraid of the flu pandemic out of season in summer. Without mutation through the epidemic, the fatality rate is equal or less than those of seasonal flu. WHO announced that the H1N1 influenza virus has moved into the post-pandemic period. However, localized outbreaks of various magnitudes are likely to continue. Another threat of flu Avian influenza viruses do not normally infect humans. However, there have been instances of certain highly pathogenic strains causing severe respiratory disease in humans. In most cases, the people infected had been in close contact with infected poultry or with objects contaminated by their faeces. Nevertheless, there is concern that the virus could mutate to become more easily transmissible between humans, raising the possibility of an influenza pandemic. H5N1 (Hong Kong, 1997) Highly pathogenic H5N1 poultry outbreaks 18 confirmed human cases, 6 deaths • Median age: 9.5 years (range 1 1-60 yrs.); 11 pneumonia cases • Case-control study: Risk factor: exposure to live poultry the week before illness (OR = 4.5, p = 0.045) • 10% H5N1 antibody seroprevalence in poultry workers • No evidence for efficient human-to to-human transmission: Wet Market: No Pandemic • 1.5 million poultry culled, markets disinfected • Poultry imports temporarily stopped from China • Surveillance: farms, markets, border • Poultry segregated, monthly market “rest days” Live bird market Dead birds Number of Patients with Avian H5N1 % A fatal human case of avian influenza H5N1 infection occurred in China in Nov 2003, and the disease expanded to South East Asia, in 2005 to world wide. Since then, 552 persons have been infected and 322 died (Fatality rate is about 60%). 120.0 100.0 Fatality rate 80.0 60.0 40.0 Alive 20.0 Death 0.0 2003 2004 2005 2006 2007 2008 2009 2010 2011 50 : Viet Nam : Indonesia : Egypt : China 45 40 35 30 25 20 HPAI H5Ni first attacked Viet Num, followed Indonesia. In 2006, 45 out of 55 patients died. Although the vaccines already had been developed, Indonesia did not available them. Indonesia government rejected the entrance of supporting parties to obtain new strain of flu virus in 2006. Developed countries stocked huge amount of H5NI vaccine, but many developing countries could never perchase them. 15 10 5 0 2003 2004 2005 2006 2007 2008 2009 2010 2011 Number of death in major epidemic countries Why the spread of H5N1 viruses among humans is limited? The epithelial cells in the upper respiratory tract of humans mainly possess sialic acid linked to galactose by α 2,6 linkages (SA α 2,6Gal). However, many cells in the respiratory bronchioles and alveoli possess SA α 2,3Gal, which is preferentially recognized by avian viruses. These facts are consistent with the observation that H5N1 viruses can be directly transmitted from birds to No sneeze ! humans and cause serious Influenza virus lower respiratory tract receptors in human. damage in humans. Virus, 56, 85-90, 2006. Nasal mucosa Bronchioli respiratorii Alveolar cell Most human cases of H5N1 avian influenza have occurred in rural or periurban areas where many households keep small domestic poultry flocks. However, defeathering or butchering of dead wild birds, especially waterfowl, is particularly hazardous in areas where Avian influenza A/H5N1 virus has been reported or is likely to occur, such as along migratory routes. The public should be advised to report, and avoid contact with, wild birds found dead. FAO developed a wet market communication pilot project. Wet Market Wild aquatic birds are considered the natural reservoir of all low pathogenic viruses(LPAI). Wild birds have probably carried influenza viruses, with no apparent harm, for centuries. A considerable circumstantial evidence suggests that migratory birds can introduce low pathogenic H5 and H7 viruses to poultry flocks. In some cases these viruses may then mutate in poultry to the highly pathogenic form. Unfortunately, the role of migratory birds in the spread of high pathogenic virus (HPAI) was not fully understood. Apr 2005, wild birds began dying at Qinghai Lake in China, where Avian Influenza Surveillance of Wild Birds numerous migratory birds congregated. Altogether, 6,345 birds from different species died in the coming weeks. This was the first reported instance of any HPAI causing mass deaths in wild birds. This event triggered world-wide spreading of H5N1. WHO strategic action plan for pandemic influenza November 2005, a meeting on avian influenza and human pandemic influenza was jointly convened by WHO, FAO, OIE, and the World Bank. The meeting agreed with two general principles and five Strategic actions. (1) preventing the emergence of a pandemic virus or, should this prove impossible, delaying the initial international spread of a pandemic (2) preparing all countries to cope with a pandemic in ways that reduce morbidity and mortality and also mitigate economic and social disruption. Strategic action 1 Reduce human exposure to the H5N1 virus 2 Strengthen the early warning system 3 Intensify rapid containment operations 4 Build capacity to cope with a pandemic 5 Coordinate global scientific research and development The plan aims to achieve two over-arching objectives: 1. to exploit all feasible opportunities to prevent the H5N1 virus from developing the ability to ignite a pandemic and, should this effort fail, 2. to ensure that measures are in place to mitigate the high levels of morbidity and mortality and social and economic disruption that can be expected during the next pandemic. Country-Level Financing and Support Framework Integrated Country Program Government Resources Domestic Private Resources Existing External Financing and Technical Assistance Potential Additional Support Grants Grants Bilateral Financing and Technical Assistance Possible World Bankadministered Trust Fund Loans, limited grants Multilateral Assistance (International Bank for Reconstruction and Development/Infocomm Development Authority) Technical Assistance, etc Regional Organisation FAO, OIE, WHO and their joint programs The World Bank, December 5, 2005: PROGRAM FRAMEWORK DOCUMENT FOR PROPOSED LOANS/CREDITS/GRANTS IN THE AMOUNT OF US$500 MILLION EQUIVALENT FOR A GLOBAL PROGRAM FOR AVIAN INFLUENZA CONTROL AND HUMAN PANDEMIC PREPAREDNESS AND RESPONSE WHO Interim Protocol: Rapid operations to contain the initial emergence of pandemic influenza The draft of interim protocol to achieve the strategic action plan for pandemic influenza was proposed on May 2006, and updated October 2007. Pandemic A/H5N1 Avian A/H5N1 Fatality rate=60% Seasonal Flu A/H1N1 A/H3N2 Index Cluster Efficiently transmissible human-to-human Reassortment in humans Containment Zone: The geographical area and population which contains the Index Cluster and where extensive interventions are applied Buffer Zone: The geographical area and population around the Containment Zone where active and complete surveillance is applied. Containment and Buffer Zones for Rapid Containment The epithelial cells in the upper respiratory tract of swine possess SA α2,6Gal and SA α2,3Gal. So, human flu virus and avian flu virus can infect swine. Reassortment of both types in swine may emerge novel pandemic virus with very high fatality rate and transmissibility. Although the control of these transmissions might be hard, Pandemic H1N1 2009 we should win this battle. extended very rapidly throughout the world, but the lethality was low. Novel Pandemic A/H5N1 could be Avian Virus Human Virus second coming of the 1919 Spanish Flu. Pandemic A/H5N1 Avian H5N1 Reassortment in swine Efficiently transmissible human-to-human OIE Disease timelines: Highly pathogenic avian influenza 2005 2006 2007 2008 2009 2010 Viet Nam Indonesia Egypt China Thailand Cambodia Turkey Azerbaijan : There is no information available on this disease : Never reported : Disease not reported during this report period : Disease suspected but not confirmed : Confirmed infection but no clinical disease : Confirmed clinical infection : Confirmed infection but limited to certain zones Small pox Smallpox is an infectious disease unique to humans(not zoonosis), caused by Variola virus. The fatality rate for flat-type is 90% or greater and nearly 100% is observed in cases of hemorrhagic smallpox. Smallpox is believed to have emerged in human populations about 10,000 BC. In the early 1950s an estimated 50 million cases of smallpox occurred in the world each year. To eradicate smallpox, each outbreak had to be stopped from spreading, by isolation of cases and vaccination of everyone who lived close by. This process is known as "ring vaccination". The global program on smallpox eradication initiated by WHO in 1958 and intensified since 1967. The global eradication of smallpox Hemorrhagic-type smallpox. was certified by a commission of eminent scientists on December 1979. Virus families not assigned to an order(65 Families) Family: Poxviridae Orthopoxvirus is a genus Subfamily: Chordopoxvirinae of poxviruses that includes Genus: Orthopoxvirus many species isolated from Camelpox virus mammals. Although Variola Cowpox virus virus infects only human, Ectromelia virus some Orthopoxviruses have Monkeypox virus the ability to infect non-host Raccoonpox virus species, such as monkeypox Taterapox virus virus. Vaccinia virus I now offer a few topics Variola virus related with small pox Volepox virus eradication. Genus: Parapoxvirus Bovine papular stomatitis virus Orf virus Parapoxvirus of red deer in New Zealand Pseudocowpox virus Monkeypox was first found in 1958 in laboratory monkeys. African squirrels might be the common host for the disease. Rats, mice, and rabbits can get monkeypox, too. Direct zoonoses Monkeypox Seven years old girl in Republic of Zaire Human monkeypox Six months later, she healed but many pockmark remained. Monkeypox is an exotic infectious disease caused by the monkeypox virus, and is usually transmitted to humans from rodents, pets, and primates through contact with the animal's blood or through a bite. Human monkey pox can be difficult to distinguish clinically from smallpox. Case-fatality ratios in Africa have ranged from 1% to 10%. It is assumed that vaccination against smallpox would provide protection against human monkeypox infection. Since the eradication of smallpox in 1979, human case increase gradually. Endemic Human Monkeypox, Democratic Republic of Congo, 2001–2004 Emerg Infect Dis. 2007 Among 136 patients, 51 (37.5%) had laboratory-confirmed MPX infection, 61 (44.8%) had laboratory-confirmed chickenpox virus infection, and 1 (0.7%) had coinfection. Age and sex distribution of patients with monkeypox Age male female <4 5–14 15–24 25–34 >35 8/12 12/22 5/17 2/9 1/6 7/21 9/19 8/13 0/8 1/7 Total 28/66 24/68 Monkeypox positive/No. cases investigated Distribution of 52 confirmed cases of human monkeypox. 762 rodents Movement of imported African rodents to pet shops and distribution of prairie dogs from a pet shop associated with human cases of monkeypox, in 2003 USA. MMWR 2003 Rodents and prairie dogs contacted with each other. African rodents were resell to Japan, but 15 already dead before arrival and lived two rodents was not infected. All 35 human cases of monkeypox were associated with prairie dogs. Cowpox and Pseudocowpox virus Milker's nodules In 1796, Dr Edward Jenner used “cowpox virus” to inoculate a patient to prevent them from contracting smallpox. Discovery of virus is in 1892(tobacco mosaic disease), so it is not as clear what virus he used for vaccine 100 years ago. In fact, milker's What is cowpox? nodule is usally caused by a parapox virus(Pseudocowpox), not by cowpox virus. Nowadays, cowpox is a rare disease. It mostly occurs in Great Britain and some European countries. Cows are no longer the main carrier of the virus; instead woodland rodents are the natural hosts of the virus who then pass it on to domestic cats. Feline cowpox virus infection Cowpox Virus Transmission from Pet Rats to Humans Germany: Outbreak including 5 patients caused by infected pet rats from the same litter in 2009. Human cowpox infections seem to be increasing. One obvious reason for an increase might be the fading cross-protective immunity to cowpox after the cessation of small pox vaccination. Human cowpox is a disease of young people, with half of all cases occurring in individuals younger than 18 years, because of their not having been vaccinated for smallpox, which may confer some protection against cowpox. 16 years old boy VARV: Variola virus CPXV: cowpox virus VACV: vaccinia virus Brazilian Vaccinia Viruses and Their Origins VACV species imported to Brazil in 1804, when human vaccine arrived at a port on the arms of slaves returning from Portugal. The species was maintained in this manner(arm to arm) and in 1887 the first animal vaccine was produced in calves. In 1963, Brazilian VACVs(Group 1, 2) was isolated from the blood of a rice rat captured near the edge of Amazon rain forest. Since then, those virus were naturally isolated from a wild rodent. In 1999, exanthematous outbreaks affecting dairy cattle and their handlers were reported. Brazilian VACVs existed before the beginning of the WHO smallpox eradication vaccination campaigns. Original animal vaccine strein imported in 1887 The virus that Dr. Edward Jenner used for vaccination derived from milker's nodule in 1796 may be Brazilian VACVs. Voyages of Christopher Columbus(1492-1504)