L15: Zika, Anthrax & COVID 19 Flashcards
Def of Emerging infectious diseases
- are βNew diseases; new problem (New threats)β caused by: A newly discovered infectious agent
- A newly identified pathogen emerged and whose incidence in humans has increased during the last 2 decades and is threatening to in the near future
Examples of Emerging infectious diseases
Def of Re-emerging infectious diseases
- are βold diseases, new problem. (New threats)β
An infectious disease was previously controlled but
once again has risen to be a significant health
problem. - This term also refers to that disease which was formerly confined to one geographic area, has now spread to other areas
Examples of that disease which was formerly confined to one geographic area, has now spread to other areas
Factors contributing to the emergence of infectious diseases
- Host factors
- Agent factors
- Environmental factors
Factors contributing to the emergence of infectious diseases
- Host Factors
Factors contributing to the emergence of infectious diseases
- Host Factors (Human demographic change)
inhabiting new areas
Factors contributing to the emergence of infectious diseases
- Host Factors (Human Behaviour)
- Unsafe sexual practices (HIV, Gonorrhoea, Syphilis)
- Changes in agricultural & food production patterns, food- borne infectious agents (E. coli)
- international travel (Influenza)
Factors contributing to the emergence of infectious diseases
- Host Factors (Human Susceptibility to infection)
Immunosuppression
Factors contributing to the emergence of infectious diseases
- Agent Factors
Factors contributing to the emergence of infectious diseases
- Agent Factors (Evolution of pathogenic infectious agents)
microbial adaptation & Change
Factors contributing to the emergence of infectious diseases
- Agent Factors (Development of Resistance to drugs)
- Wrong prescribing practices
- Non-adherence by patients
- Counterfeit drugs
- Use of anti-infective drugs in animals & plants
Factors contributing to the emergence of infectious diseases
- Agent Factors (Risistance of vectors to pesticides)
β¦.
Factors contributing to the emergence of infectious diseases
- Environmental Factors
Factors contributing to the emergence of infectious diseases
- Environmental Factors (Climate & changing ecosystems)
- Deforestation forces animals into closer human contact increase possibility for agents to breach species barrier between animals & humans
Factors contributing to the emergence of infectious diseases
- Environmental Factors (natural disasters & related outbreaks)
Malaria, Cholera
Factors contributing to the emergence of infectious diseases
- Environmental Factors (Global warming)
spread of Malaria, Dengue, Leishmaniasis, Filariasis
Factors contributing to the emergence of infectious diseases
- Environmental Factors (Economic development & Land use)
urbanization, deforestation
Factors contributing to the emergence of infectious diseases
- Environmental Factors (Technology & industry)
food processing & handling
Factors contributing to the emergence of infectious diseases
- Environmental Factors (Breakdown of public health measure)
war, unrest, overcrowding
Factors contributing to the emergence of infectious diseases
- Environmental Factors (Uncontrolled Urbanization &Population displacement)
Problem of refugees & displaced persons
Control of Emerging and Re-emerging Diseases
- Controlling possible causes
- Role of doctors in prevention
- Public health measures
- Response of the WHO
Control of Emerging and Re-emerging Diseases
- Controlling Possible Causes
Control of Emerging and Re-emerging Diseases
- Role of Doctors in Prevention
Control of Emerging and Re-emerging Diseases
- Public Health Measures
Control of Emerging and Re-emerging Diseases
- Response of WHO
Def of Zika Virus
a mosquito-borne flavivirus
1st Case of Zika Virus
The very 1st known case of Zika fever was in a rhesus monkey in the Zika Forest in Uganda in 1947
1st Human Case of Zika Virus
The 1st human cases were reported in Nigeria in 1954
Outbreaks of Zika Virus
- A few outbreaks have been reported in tropical Africa and in some areas in Southeast Asia.
- The 1st major outbreak, with 185 confirmed cases, was reported in 2007 in the Yap Islands of the Federated States of Micronesia.
- In 2013 another large outbreak was reported in French Polynesia
- Mosquito-borne Zika virus is suspected to be the cause of 2,400 cases of microcephaly and 29 infant deaths in Brazil in 2015
Zika Virus & Brazil
- Mosquito-borne Zika virus is suspected to be the cause of 2,400 cases of microcephaly and 29 infant deaths in Brazil in 2015
Epidemic Threshold of Zika Virus
Viral load in body β₯4800 viral copies triggered dissemination and β₯12,000 viral copies set out transmission
Zika Virus in egypt
No detected cases in the last outbreak
Possible Case of Zika Virus
Not applicable
Probable Case of Zika Virus
Confirmed Case of Zika Virus
Causative Agent of Zika Virus
ZIKa virus
Anmal Hosts of Zika Virus
monkeys, domestic sheep, goats, horses, cows, ducks, rodents,
bats.
MOT of Zika Virus
IP of Zika Virus
3β14 days
Infectivity Period of Zika Virus
ranges from a few days to 1 week (Virus remains in semen and urine longer than in blood )
General Prevention of Zika Virus
βΆ Protection against mosquito bites (refer to general epidemiology)
β· Protection against Sexual transmission (refer to general epidemiology)
Specific Prevention of Zika Virus
No vaccine is yet available
Def of Anthrax
a serious zoonotic infectious disease caused by gram-positive, rod-shaped bacteria
Type of anthrax bacteria
gram-positive, rod-shaped bacteria
Global Epidemeology of Anthrax
Endemic in parts of South and Central America, Southern and Eastern Europe, Asia, Africa, the Caribbean and the Middle East.
Latest outbreaks of Anthrax
- 2001; letters containing anthrax spores were
mailed to several news media offices and two U.S. Senators, killing five people and infecting 17 others (biological weapon). - 2014; in India resulting in 7 deaths.
- 2016; in Siberia, Russia resulting in 2300 deaths among animals.
- 2018; in France (cattle Farms)
Compare between Cutaneous, GI & Inhalational Anthrax in terms of:
- Case Definition
- Occurrence
- CFR
- MOT
- IP
Causative Agent of Anthrax
Bacillus anthracis
Reservoir of Anthrax
βΆ Infected animals (grazing herbivorous animals)
β· Soil (Spores)
Biologocal Terrorism & Anthrax
(Estimated Effects)
- 50 kg of spores among urban area of 5 million leads to 250,000 cases of anthrax & 100,000 deaths
Infectivity period of Anthrax
B. anthracis spores can remain viable and infective in soil for years and maybe decades
General Prevention of Anthrax
Specific Prevention if Anthrax
Vaccination of Anthrax
Cell-Free Filtrate
Dose of Vx of Anthrax
Immunization series (5 IM injections over 18-week period with annual booster)
Indications of Vx of Anthrax
At risk groups (Veterinarians, Lab workers, Livestock
handlers, Military personnel)
SE of Vx of Anthrax
no serious side effects
Case Control Measures for Anthrax
(refer to general epidemiology) + Cutaneous/gastrointestinal anthrax Ciprofloxacin, penicillin or doxycycline are the drugs of choice, usually given for 7β10 days
Contact Control Measures for Anthrax
(refer to general epidemiology)
Control Measures for Anthrax in bioterrorist attacks
- involving aerosolized anthrax where the risk is high, ciprofloxacin or doxycycline are recommended and should be given for at least 60 day
Def of Coronaviruses
- Coronaviruses are enveloped RNA viruses that cause respiratory illnesses of varying severity from the common cold to fatal pneumonia.
Many coronaviruses are known to cause disease in humans
..
Coronaviruses causing Common cold
229E, OC43, NL63 & HUK1.
Coronaviruses causing COVID19
SARS-CoV2 is a novel coronavirus identified as the cause of coronavirus disease 2019 (COVID-19) that began in Wuhan, China in late 2019 and spread worldwide in a widespread pandemic.
Coronaviruses causing MERS
MERS-CoV was identified in 2012, cause of Middle East respiratory syndrome (MERS)
Coronaviruses causing SARS
SARS-CoV was identified in 2002, cause of an outbreak of severe acute respiratory syndrome (SARS).
These coronaviruses that cause severe respiratory infections are β¦β¦.. pathogens, which begin in infected animals and are transmitted from animals to people
zoonotic
Global Epidemeology of COVID 19
- As of 20 September 2021, more than 228 million cases and 4.69 million deaths have been confirmed, making it one of the deadliest pandemics in history.
- Lowest case fatality rate is detected in Singapore 0.1%
- highest is detected in Yemen (19%)
National Epidemeology of COVID 19
Number of confirmed cases is 296,929 with deaths 16,970 till 20 sept 2021 with case fatality rate 5.7%
Epidemic Threshold of COVID 19
diagnosing one or more cases of COVID-19
Suspected case of COVID 19
A person who meets the clinical AND epidemiological criteria
Clinical Criteria of COVID 19
Symptoms in COVID 19
Epidemeological criteria of COVID 19
Probable Case of COVID 19
Cobfirmed Case of COVID 19
Causative agent of COVID 19
novel coronavirus SARS-CoV-2 Variants (alpha, beta, gamma & delta)
MOT of COVID 19
- Animals to humans transmission.
- Person-to-person spread: occurs through droplet infection (direct or indirect)
IP of COVID 19
1β14 days
Infectivity Period of COVID 19
- 1 to 3 days before symptoms start, and in the first 7 days after symptoms begin.
But some people may remain infectious for longer
Susceptibility to COVID 19
Dx of COVID 19
General Prevention of COVID 19
(Standard Precautions & Transmission-Based Precautions)
Specific prevention of COVID 19
Vaccinations:
- mRNA Vx
- Vector Vx
- Inactivated Vector Vx
Concept of mRNA vaccines
- contain the genetic instructions for making the COVID-19 spike protein, this protein is found on the surface of the virus that causes COVID-19
Examples of mRNA vaccines
(Pfizer Ultra Frozen Vaccine / Moderna Frozen Vaccine)
Concept of Vector vaccines
contain a modified version of a different virus than the one that causes COVID-19. Inside the shell of the modified virus, there is material from the virus that causes COVID-19
Examples of Vector vaccines
(AstraZeneca/COVISHIELD)
Concept of Inactivated virus vaccine
- Inactivated vaccines consist of virus particles that
have been grown in culture and then are killed using a method such as heat or formaldehyde to lose disease producing capacity, while still stimulating an
immune response
Examples of Inactivated virus vaccine
(Sinopharm & Sinovac)
Mild to Moderate Case Control Measures in COVID-19
Severe Case Control Measures in COVID-19
Contact Control Measures in COVID-19
Epidemic Control Measures in COVID-19
Refer to general epidemiology + Mass vaccination