Global warming and infection Flashcards
What is anthrax?
Anthrax is an infectious disease caused by the bacterium Bacillus anthracis.
In what way can the outbreaks of anthrax be related to global warming?
The anthrax bacteria can form dormant (inactive) spores and live in the soil for a long time, even decades. When the spores get into a person, or animal, they can be activated and turn into actively growing cells.
A heatwave was reported to melt the permafrost in Siberia exposing the carcass of a reindeer infected with anthrax. This event is believed to be the cause of the first anthrax outbreak in Siberia in 40 years.
What are thought to be the main climate change effects? In what ways can these be related to the increase of emerging infectious diseases?
Increased temperature, rising sea levels and increased precipitation (rain, snow, sleet or hail).
Storms and flooding cause displacement, morbidity and mortality and can thus increase the spread of infectious diseases. (Especially diseases with waterborne agents.)
Many scientists point to global warming as a factor in the spread of malaria and other vector-borne infectious diseases.
What is meant by “vector biology”?
Traditionally in medicine, a vector is an organism that does not cause disease itself but which spreads infection by conveying pathogens from one host to another. Species of mosquito, for example, serve as vectors for the deadly disease Malaria.
What are the two main health risks related to flooding because of tropical storms, heavy rains, melt water and tsunamis?
1) Increase in food- and waterborne diseases, such as cholera, typhoid fever, hepatitis A and leptospirosis.
2) Increase in insect-borne / vector-borne diseases, such as malaria, dengue fever, Japanese encephalitis, yellow fever and West Nile fever.
How is leptospirosis spread? What are some symptoms of leptospirosis?
Leptospirosis is also known as rat fever, and spreads through excreta of rodents, particularly rats.
Symptoms of leptospirosis include high fever, muscle ache, chills, headache, vomiting and diarrhea, abdominal pain, jaundice and rash.
Hvorfor er infeksjoner med vibrio vilnificus så sjeldent i Norge?
Vibrio vulnificus lever i vann og sediment. Den trives godt i varmt vann, gjerne over 20°C.
(Alvorlige sykdom forekommer oftest nær Taiwan, Sør-Korea, Japan og i Mexicogolfen. I senere år er det rapportert flere tilfeller med alvorlige infeksjon med Vibrio vulnificus hos personer som har badet i nordiske kystområder. I løpet av den varme sommeren 2018 var det sju personer som ble alvorlig syke med denne infeksjonen i Norge.)
Disease carrying vectors are often insects. Name some examples of such vectors.
What types of infectious agents does these vector carry?
Mosquitoes, ticks, fleas, black flies and sand flies are examples of such.
The vectors can carry protozoa, bacteria and viruses.
What is an arboviral disease?
Name some examples of arboviral diseases.
It is an infectious viral disease spread through the bite of arthropods (insects).
Some examples are zika virus, dengue fever and yellow fever.
What are some examples of bacterial vector-borne diseases?
Tularemia, Lyme borreliosis and plague.
What is the name of the bacterium that causes plaque? What antibiotics can be used to treat it?
The name of the bacterium is Yersinia pestis.
Antibiotics used for treatment are gentamicin, doxycyklin, and ciprofloxacine.
Global warming is believed to be increasing the incidence of a number of tick- and mosquito-borne disease. In which ways is the spread of the diseases expanding?
The diseases are expanding northward and to higher altitudes.
In what ways is malaria climate sensitive?
Temperature effects the lifespan of the mosquitoes, how fast they mature, how often they bite and how fast the parasite inside the mosquito matures.
Rainfall is essential as it creates a breeding ground for the mosquitoes - mosquito eggs must be laid in water.
Humidity effects the lifespan of the mosquitoes.
What is thought to be the optimal temperature for malaria transmission?
25 degrees Celsius.
Transmission decreases significantly when the temperature is above 28 degrees Celsius.
What are the three reasons the Zika outbreak is believed to related to climate change?
1) Hotter temperature makes mosquitoes hungrier. The more the mosquitoes feed the likelier their are to get infected and spread the disease.
2) Warm air incubates the virus faster. Thus more mosquitoes will be alive longer while contagious.
3) Mosquito territory expands are the climate warms.
