What does propagated outbreak mean?
A propagated outbreak results from transmission from one person to another. Usually, transmission is by direct person-to-person contact, as with syphilis.
Is Covid 19 a propagated epidemic?
In conclusion, besides the imported cases, the pattern of local transmission of COVID-19 was a mixture of the propagated epidemic and the common-source outbreak in Tianjin. Local transmission of COVID-19 mainly occurred within families and a poorly ventilated public place in Tianjin.
What are 2 types of outbreaks?
Types of Outbreak
- Point Source Outbreaks. Common source outbreaks where the source has infected cases at one particular geographical location, during a short period of time, are called ‘point source outbreaks’.
- Continuing common source outbreaks.
- Propagated outbreaks.
What is the difference between common source epidemic and propagated epidemic?
common source outbreak: a type of epidemic outbreak where the affected individuals had an exposure to a common agent. propagated outbreak: a type of epidemic outbreak where the disease spreads person-to-person. Affected individuals may become independent reservoirs leading to further exposures.
Is Ebola a propagated epidemic?
Ebola is an example of a propagated epidemic. The graphs of new cases over time in West Africa are a combination of many mini outbreaks happening simultaneously.
What is Holoendemic in epidemiology?
A holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic …
What is an emerging disease?
Emerging infectious diseases can be defined as infectious diseases that have newly appeared in a population or have existed but are rapidly increasing in incidence or geographic range, or that are caused by one of the NIAID Category A, B, or C priority pathogens.
Is COVID-19 a epidemic or pandemic?
The number of people affected was exponentially growing and the World Health Organization (WHO) upgraded COVID-19 to a pandemic in March 2020. Pandemics are known to cause large-scale social disruption, economic loss, and general hardship, and COVID-19 has been no exception.
Is cholera A propagated epidemic?
Cholera has an incubation period of 1-3 days, and even though residents began to flee when the outbreak erupted, you can see that this outbreak lasted for more than a single incubation period. This suggests an ongoing source of infection, in this case the Broad Street pump. Propagated (or progressive source) epidemic.
What is an example of holoendemic?
Other examples of holoendemic diseases include ocular trachoma in certain areas in sub-Saharan Africa, where virtually all children in those populations have been infected, and hepatitis B in areas of the Marquesas Islands.
What is the difference between hyper endemic and holoendemic?
One of the differences between hyperendemic and holoendemic diseases is that hyperendemic diseases show a seasonally intense transmission in all age groups with a period of low or no transmission, whereas in holoendemic diseases, there is perennial (year-round) high level of transmission predominantly among young …
What are three emerging infections?
Emerging diseases include HIV infections, SARS, Lyme disease, Escherichia coli O157:H7 (E. coli), hantavirus, dengue fever, West Nile virus, and the Zika virus.
What are vector-borne diseases?
Vector-borne diseases are infections transmitted by the bite of infected arthropod species, such as mosquitoes, ticks, triatomine bugs, sandflies, and blackflies. Arthropod vectors are cold-blooded (ectothermic) and thus especially sensitive to climatic factors.
When did COVID-19 start?
It was initially reported to the World Health Organization (WHO) on December 31, 2019. On January 30, 2020, the WHO declared the COVID-19 outbreak a global health emergency. On March 11, 2020, the WHO declared COVID-19 a global pandemic, its first such designation since declaring H1N1 influenza a pandemic in 2009.
Why do epidemics end?
Indeed, few epidemic diseases are eradicated. Far more often, an epidemic is declared to have ended once the disease falls to endemic levels, when it becomes an accepted, manage- able part of normal life in a given society.
What is continuous source outbreak?
This is a continuous common source epidemic in which exposure to the source is prolonged over an extended period of time and may occur over more than one incubation period. The down slope of the curve may be very sharp if the common source is removed or gradual if the outbreak is allowed to exhaust itself.
What are some examples of common source outbreak?
A common-source outbreak occurs when a group of people get sick after being exposed to a virus, bacteria, toxin, or other infectious agent from the same source. For example, a common-source outbreak happens when a group of people get sick after eating the same contaminated food at the same restaurant on the same day.
What is holoendemic in epidemiology?
Is malaria a holoendemic?
Holoendemicity is frequently seen with malaria, specifically the strain caused by Plasmodium falciparum, in several regions of sub-Saharan Africa (one study found that 98.6% of the population had traces of the pathogen within a 4 month period).