Vectors and transmission and emerging diseases

Question 1

List infections spread by aedes mosquioto and (intermediate hosts)

Answer 1

Dengue
Zika
Yellow fever
Chikungunya
(all non-human primates)

Also
La crosse virus
Mayaro virus
Cache Valley Virus (in america, seen in farm animals)
Wesselsbron (place is SA, in subsahan africa- in cattle, causes mild disease

These mosquitoes are active throughout the day, especially during the hours of highest activity: mid-morning and late afternoon to twilight

Note rift valley fever, WEE spread by aeds and culex

Question 2

List infections spread by culex mosquito (and other hosts)

Answer 2

West nile (birds)
JE (Pigs)
St Louis encephalitis
Usutu

-all are more encephalitisy ones

Question 3

What is the vector for oropouche virus?

Answer 3

A midge Culicoides paraensis
Oropouche presents similarly to Dengue

Outbreaks of Oropouche fever virus have been reported from rural and urban communities of Peru, Brazil, Ecuador, Panama, Peru, and Trinidad and Tobago

Oropouche is an orthobunyavirus

Question 4

What is the definition of an emerging infection (4 points)

Answer 4

1) Previously unknown infectious agent
2) Previously known agent which has become newly identifed as causing infections
3) Spread to a new geopraphic area
4) Re-mergence where incidence has declines and has now re-appeared

Question 5

Viral infections spread by ticks in america

Answer 5

Heartland virus
Powassan Virus
Bourbon virus
Colarado Tick fever

Note Powassan is the only one that causes encephalitis I think

Question 6

Viral infections spread by mosquitos in America

Answer 6

West Nile
La crosse virus
Eastern Equine
Cache Valley
Jamestown virus
St Louis encephalitis
EEE (30% mortality in neuroinvasive disease)
WEE (low mortality- 4%, Low and Western have a W in them)

Note: La crosse virus is commonest cause of arthopod encephalitis in children (second is west nile, unlike in adults where west nile is more common)

Question 7

Which is the vector for lassa fever

Answer 7

The multimammate rat

Question 8

What is the vector for toscana virus

Answer 8

Sandly (phlebotomis)
Can cause encephalitis

Question 9

What family of virus is Chindipura? What country is it found in and when was the last out break

Answer 9

India in 2013

Rhabdoviridae

Question 10

What is the case fatality of JE neuro-invasive disease

Answer 10

30%

Question 11

Causes of arthropod vector spread encephalitis in Australia

(not inclusive, got confused in writing this!)

Answer 11

JE- culex
Murray valley (20% mortality)- culex
Kunjin (v similar to west nile)

(note Hendra is in australia but is from direct contact with horses and bats)

Question 12

Microcephaly is found on a fetal US in a lady who visited puerta rico. what are the next steps?

Answer 12

Consideration amniocentesis to
test for the virus using RT-PCR

Note a small fetus head is 2 standard deviations below the norm. Usually you want to see some more other abnormalities for Zika (including Cerebral and/or ocular calcifications Oligohydramnios
Ventriculomegaly Talipes
Periventricular cysts
Callosal abnormalities…lots of others)

Sensitivity for this test is not determined

Question 13

What is the host of Seol Virus

Answer 13

Rats- Rattus norvegicus (Norway and black rates

This is the only hanta in europe spread by rats

The rest are field mice (Haantan and Dubrava) and
Bank Voles (Puumala) or common vole (Tula)

Question 14

Describe pitfalls of MPox testing in the DRC strains

Answer 14

Deletion in gene of Clade 1, which gives false positive clade 2 results- In DRC

Question 15

Hantavirus PCR in blood is detectable often T/F

Answer 15

F
Biphasic illness, PCR may be positive for prodrome only

Incubation period is 2 weeks

Causes capillary leakage
- in lungs presents with pleural effusions or oedea
- in kidneys: acute haemorrhagic tubular interstitial nephtitis= swollen kidneys

Question 16

Age cut off for conisering acivlovir therapy in babies as prophylaxis

Answer 16

Can only give from 4 weeks (unless mum had chicken pox from day 4 before to two days after borth)

<7 days old and exposed- give VZIG

Between 7 days and 4 weeks
- Offer VZIG if baby is high risk

(in hospital since birth + <28 weeks, <1000gm, severe congenital condition)

Question 17

Treatment of nenonate with varicella

Answer 17

Aciclovir 20mg/kg TDS for 7 days

Question 18

What is Langya virus

Answer 18

Henipavirus (-SS RNA, paramyxoviridae)

China

Fever, fatigue- mild illness. No spread between people, not found in bats

Question 19

JE
1) incubation period
2) T/F: most cases are asymptomatc or mild

Answer 19

1) 14 days
2) T: 1 in 250 has severe symptoms, case fatality in this group is 30%

Question 20

Viral infections from Camels

Answer 20

MERS (?countries)
HEV (genotype 7 and 8)

?more

Question 21

What percentage of West Nile virus infected are asymptomatic

Answer 21

80%

Less than 1% infected develop neuroinvasve disease

Incubation period is 14 day

ACDP Group 3

Note chik has attack rate of 75%

Question 22

Contibuters to west nile virus spread in europe

Answer 22

Migratory birds
Habitats of culex
Land use changes (urbanisation and agriculture) , bring humans closer to mosquitos and birds
Global warming- increased temperature increases abundance and shortens generational time of mosquitos

• In 2022, there were 1133 confirmed and probable cases of human West Nile virus infection. This represented an increase of 631.8% in locally acquired
  cases, compared with 2021.
• During the past 5years, two unusually intense transmission seasons were documented in 2018 and 2022,
• West Nile virus extended its geographical area, affecting birds and equines, and emerged during 2022 on the Atlantic coast in France. Its incidence increased in the North of Germany and
  in the South of Italy.

Question 23

Vector for TBE

Answer 23

Ixodes Tick

Also milk products

In Europe, TBE is endemic in several central, northern, and eastern countries. Some countries experienced novel autochthonous TBE in humans, like the Netherlands in 2016 [28], Belgium in 2018 and 2020 [29,30], and the United Kingdom in 2019 [31]. Since 2017, there has been a gradual increase in reported TBE cases in the European Union/European Economic Area (EU/EEA)

Question 24

Ebola virus lis and locations incomplete

Answer 24

Zaire ebolavirus (Ebola virus; EBOV), Sudan ebolavirus (SUDV), Bundibugyo ebolavirus (BDBV), Taï Forest ebolavirus (TAFV), Reston ebolavirus (RESTV), and Bombali ebolavirus (BOMV). EBOV, SUDV, and BDBV all cause severe Ebola virus disease (EVD) in humans with high case fatality rates.

Question 25

From which countries do you need to worry about rabies in foxes (incomplete), that would otherwise be low risk for rabies

Answer 25

Canada and America (also racoons, skunks)
Croatia, slovakia, slovenia, estonia, latvia, hungry

Question 26

What is in the JE complex

Answer 26

Flavivirus spread by culex

West nile
JE
Usutu
Murray valley
Kunjin
St Louis

Question 27

Place in world
Case fatality
Host

Laguna Negra virus

Answer 27

South America
Vesper mouse
10%

Question 28

Place in world
Case fatality
Host

Choclo

Answer 28

Panama

Pigmy rice rat
15%

Question 29

Place in world
Case fatality
Host
Araraquara virus

Answer 29

Hairy-tailed bolo mouse
45%
Brazil

Question 30

Place in world
Case fatality
Host
Juquitiba virus

Answer 30

Pigmy rice rat
45%

Question 31

High mortality Hantas AASJ

Answer 31

Andes
Sin Nombre
Juquitiba
Araraquara

Question 32

Dobrava

Answer 32

Yellow necked mouse
Balkans
10% case mortality