HIV-2 Flashcards

1
Q

Which HIV type is most common HIV-1 or HIV-2?

A

HIV-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the relationship between HIV-2 and simian immunodeficiency virus (SIV)?

A

Closely related to SIV in sooty mangabeys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the difference in the relationship between HIV-1, HIV-2 and SIV?

A

HIV-1 related to SIV in chimpanzees

HIV-2 related to SIV in sooty mangabeys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the prevalence worldwide of HIV-2?

A

1-2 million

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where is HIV-2 endemic?

A

West Africa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many subtypes of HIV-2?

A

NINE (9)

Only A & B epidemic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the limitations of evidence in HIV-2 prevalence and natural course.

A

Cohort and treatment studies - group A only
Small worldwide number
Rapid HIV test often does not differentiate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the the pathogenicity of HIV-2?

A

Most untreated individuals will have disease progression

Slower progression than HIV-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe limitations of evidence for treatment of HIV-2

A

ART developed for HIV-1 group M
Limited in vitro evidence
Evidence based on cohort and observational studies only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the difference between HIV-1 and HIV-2 and transmission?

A

HIV-2 lower risk of horizontal and vertical transmission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is transmission less likely with HIV-2 vs HIV-1?

A

Lower plasma viral load, often undetectable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the relationship between CD4 and AIDS in HIV-2?

A

AIDS defining illness can occur at higher CD4 count

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the progression of CD4 in HIV-2 vs HIV-1?

A

CD4 count in HIV-2 slower decline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the disease trajectory in HIV-2 vs HIV-1?

A

HIV-2 progresses at half the rate of HIV-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Is there any difference in clinical disease/AIDS-defining illness due to HIV-2 vs HIV-1?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which TWO class of ART can resistance more easily develop?

A

NRTI

PI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Does HIV-2 protect against HIV-1?

A

No but may delay clinical progression of HIV-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What type of animal SIV is the HIV-2 origin?

A

SIV smm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What human contact is there with sooty mangabeys in West Africa?

A

Hunted for FOOD

Kept as PETS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When did SIVsmm likely jump from sooty mangabey to human?

A

1905-1945

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What was the prevalence of HIV-2 in West Africa in 1980s?

A

> 1% in some parts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where in West Africa reported the highest prevalence of HIV-2?

A

Guinea-Bissau

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the prevalence of HIV-2 in GUinea Bissau?

A

8%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the prevalence of HIV-2 in over 40 year olds in GUinea Bissau?

A

20%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Dissemination of HIV-2 outwith West Africa is attributed to which event and which country?

A

War of Independence (1963-1974)

Portugal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which countries in Europe have the highest prevalence of HIV-2?

A

FRANCE

PORTUGAL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the number of people living with HIV 2 in FRANCE?

A

1000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the number of people living with HIV 2 in PORTUGAL?

A

2000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the possible reasons for decreasing prevalence of HIV-2?

A

lower transmission rate
change in risk behaviour
reduced healthcare associated infection
competition with HIV-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

When should ART be started in HIV-2?

A

At new diagnosis

evidence to support limited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Why is adherence so important in ART for HIV-2?

A

INTRINSIC resistance therefore less options
LOWER THRESHOLD for resistance
LIMITED SWITCH options

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Why is regular CD4 monitoring encouraged for HIV-2?

A

VL is often undetectable and therefore does not help with monitoring of therapy efficacy and health status

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is general pathway of testing and confirming HIV-2 infection?

A

4th generation Ag/Ab SCREENING
at least 2 CONFIRMATORY tests
1 test that can DIFFERENTIATE between HIV1 and HIV2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the limitation of the 4th generation Ag/Ab test for HIV in context of HIV-2?

A

p24 antigen detective designed towards HIV-1

therefore this test is only ANTIBODY test for HIV-2 and has no utility in early infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Is there an avidity test of HIV-2?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the limitation of the HIV-2 RNA viral load test?

A

often undetectable therefore no use if trying to confirm HIV-2 infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What additional test can be used to confirm HIV-2, if screen is indeterminate and viral load undetectable?

A

measure HIV-2 PROVIRAL DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the proportion of PLW HIV-2 who have undetectable viral load and are ART naive?

A

25-40%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Can PLW HIV-2 progress even if viral load undetectable?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the relationship between HIV-2 detectable viral load and clinical progression?

A

Higher risk or rate of progression c/w undetectable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Which HIV-2 subtype is harder to measure viral load for?

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is the discordance observed between viral load and clinical progression in subtype B HIV-2?

A

Clinical progression more regularly observed with undetectable VL c/w subtype A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Why might clinical progression be more likely in subtype B HIV-2 and undetectable VL?

A

Harder to test for VL for subtype B therefore may be incorrectly measured as undetectable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What type of resistance testing if available for HIV-2?

A

Genotypic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

At what viral load level can resistance testing be performed on HIV-2?

A

> 500copies/ml

46
Q

What 2 classes of ART is HIV-2 naturally resistant?

A
NNRTIs
Fusion inhibitors (enfuvirtide)
47
Q

Describe the method of genotypic HIV-2 resistance testing.

A
  • EXTRACTION viral RNA
  • REVERSE TRANSCRIPTION of RNA to complementary DNA
  • PCR AMPLIFICATION of cDNA
  • ANALYSED for mutations
48
Q

Sanger resistance method is used for HIV-2, what level do mutations have to be present in the viral population to be detected?

A

> 15% of viral population

49
Q

Why should ART be given to PLW HIV-2?

A

Overall evidence suggests, without ART:

  • HIV-2 will progress to AIDS
  • Life expectancy reduced by 10 years
50
Q

Is ART recommended in HIV-2 infection?

A

YES

Although no consensus across world

51
Q

When monitoring dual HIV-1 and 2 infection what is essential to check?

A

viral load and resistance of EACH virus

52
Q

What is the definition of primary HIV infection?

A

HIV infection within maximum of 6 months from estimated time of HIV transmission

53
Q

What is the rationale for immediate ART start in primary HIV-2 infection?

A

Improved mortality and morbidity regardless of CD4 (HIV-1 trials)
Reduce transmission
Limit viral reservoir

54
Q

When should ART be started in HIV-2 and hepatitis B co-infection?

A

Either as HIV-2 start
or
if independent HBV treatment criteria is met
ART should cover both viruses

55
Q

Should ART be started in HIV-2 with detectable VL?

A

YES

detectable VL strong indication for ART start

56
Q

Why is low level viraemia in HIV-2 of concern?

A

VL HIV-2 shown to be 10 to 100 times lower than HIV-1 when matched for CD4 cell count, ie impact of CD4 even at low level

57
Q

What is the definition of Advanced HIV disease in adults?

A

CD4<200

Stage 3 or 4 at presentation

58
Q

When should ART be started in HIV-2 with current or past history of an indicator condition?

A

IMMEDIATE start, regardless of VL

59
Q

HIV-2 infection + MALE sex is associated with increased risk of what?

A

AIDS
Loss to follow up
Mortality

60
Q

At what age is there an higher overall mortality in HIV-2?

A

> 45 years

61
Q

What EIGHT specific settings is ART recommended in HIV-2?

A

1) PRIMARY infection
2) CO-INFECTION with HBV
3) DETECTABLE viral load
4) CD4 <500
5) ADVANCED HIV (CD4 <200)
6) OPPORTUNISTIC infection
7) INDICATOR condition
8) COMORBIDITY - esp cardio, renal, hepatic

62
Q

What is the recommended combination ART for HIV-2?

A
2x NRTI
\+
1x 2nd generation INSTI 
or
1x ritonavir-boosted PI
63
Q

What is the first line NRTI regimen for HIV-2?

A

Tenofovir disoproxil
+
Emtricitibine

64
Q

Can TAF be used instead of TDF for HIV-2?

A

YES

65
Q

Why is tenofovir preferred over abacavir for HIV-2?

A

TDF great activity in presence of resistance

66
Q

Studies of abacavir use in HIV-2 are generally in the context of what combination therapy?

A

Triple NRTI with zidovudine + lamivudine

67
Q

Why are zidovudine and stavudine not recommended as first line treatment of HIV-2?

A

MITOCHONDRIAL toxicity

68
Q

Why are didanosine not recommended as first line treatment of HIV-2?

A

MITOCHONDRIAL toxicity

HEPATIC toxicity

69
Q

What are the TWO preferred 3rd agents that can be considered for HIV-2?

A

DOLUTEGRAVIR

DARUNAVIR/ritonavir

70
Q

What 3 INSTIs can be alternative to DTG for HIV-2?

A

BICTEGRAVIR
RALTEGRAVIR
ELVITEGRAVIR/cobicistat

71
Q

Can cobicistat be used as an alternative pharmacokinetic enhancer to ritonavir for HIV-2?

A

YES

72
Q

What is the recommended DOSE of DOLUTEGRAVIR for HIV-2?

A

50mg TWICE daily

73
Q

When might DOLUTEGRAVIR ONCE daily be used for HIV-2?

A

If undetectable viral load prior to starting ART

74
Q

Why is dolutegravir generally preferred over darunavir/r for HIV-2?

A

Better TOLERABILITY

REDUCED drug-drug interaction

75
Q

Why is darunavir the preferred PI in HIV-2?

A

Better TOLERABILITY and TOXICITY profile

76
Q

What is the recommended DOSE of DARUNAVIR/r for HIV-2?

A

600mg/100mg TWICE daily

77
Q

When might DARUNAVIR/r ONCE daily be used for HIV-2?

A

If undetectable viral load prior to starting ART

78
Q

What is the potential disadvantage of using bictegravir for HIV-2?

A

available only as combination SINGLE TABLET REGIMEN

Unable to increase dose

79
Q

What are the disadvantages of not being able to increase dose of bictegravir for HIV-2?

A

May be less effective if detectable viral load
or
past history of treatment failure on 1st gen INSTI

80
Q

What evidence of INSTI resistance from RALTEGRAVIR use is there for HIV-2?

A

ONE RETROSPECTIVE study

relatively FREQUENT emergence

81
Q

How should RALTEGRAVIR be dosed for HIV-2?

A

TWICE daily

82
Q

Other than darunavir, what other PIs can be used for HIV-2?

A

LOPINAVIR/ritonavir

SAQUINAVIR/ritonavir

83
Q

To which PIs is there reduced phenotypic sensitivity and therefore should not be used for HIV-2?

A

ATAZANAVIR
FOSAMPRENAVIR
TIPRANAVIR

84
Q

Through what mechanism is HIV-2 intrinsically resistant to NNRTIs?

A

DIFFERENT STRUCTURE of NNRTI-binding pocket in HIV-2 c/w HIV-1

85
Q

Other than NNRTI what other ART is HIV-2 INTRINSICALLY resistant too?

A

FUSION inhibitor

ENFUVIRITIDE

86
Q

Can MARAVIROC be used for HIV-2?

A

MAYBE
Evidence IN VITRO
No clinical experience

87
Q

How often should CD4 count be checked in HIV-2 infection for those NOT on ART and those ON ART?

A
BASELINE
AFTER START:
1 month 
3 month
6 month
THEN
3-6 monthly thereafter
88
Q

What resistance testing should be performed at baseline on HIV-2?

A

NRTI
PI
INSTI

89
Q

How often should VIRAL LOAD be checked in HIV-2 infection for those NOT on ART?

A

SIX (6) monthly

90
Q

How often should CD4 count be checked in HIV-2 infection for those NOT on ART?

A

Baseline

3-6 months

91
Q

How often should VIRAL LOAD be checked in HIV-2 infection if DETECTABLE prior to ART start?

A
1 month 
3 month
6 month
then
3-6 monthly
92
Q

How often should VIRAL LOAD be checked in HIV-2 infection if UNDETECTABLE prior to ART start?

A

1 month

6 month

93
Q

When should resistance be checked in HIV-2 outwith baseline?

A

if previously undetectable and becomes repeatedly detectable

94
Q

What is the annual average CD4 cell loss in HIV-2 c/w HIV-1?

A

HIV-2 ELEVEN (11) cells/mm3/year

HIV-1 FORTY NINE (49) cells/mm3/year

95
Q

Is the CD4 cell count more rapid for HIV-2 or HIV-1?

A

HIV-2

96
Q

Is CD4 cell count response to ART poorer in HIV-2 or HIV-1?

A

HIV-2

97
Q

What factor makes CD4 cell count response poorer in HIV-2 after starting ART?

A

LOW nadir CD4 cell count

98
Q

Why is CD4 cell count monitoring potentially more important in HIV-2 than HIV-1 even if on treatment?

A

HIV-2 viral load often UNDETECTABLE at start of ART but can still result in CD4 loss

99
Q

Is virological response to ART SLOWER in HIV-2 or HIV-1?

A

HIV-2

100
Q

In PREGNANCY, what is the preferred 3RD agent for ART in HIV-2?

A

DARUNAVIR/r

101
Q

Why is DARUNAVIR preferred 3rd agent in PREGNANCY?

A

more clinical experience

102
Q

What ART typically consider safe in pregnancy + HIV-1 cannot be used in HIV-2?

A

EFAVIRENZ

ATAZANAVIR

103
Q

Why can atazanavir and efavirenz NOT be used in pregnancy + HIV-2?

A

Resistance (not suitable in any clinical scenario as Rx for ART)

104
Q

What is the risk of VERTICAL transmission for UNTREATED HIV-2?

A

0.6-4%

105
Q

Is VERTICAL transmission rate lower or higher for HIV-2 vs HIV-1?

A

LOWER

106
Q

What are the BENEFITS of starting ART in PREGNANCY for HIV-2?

A

avoid detectable viral load in pregnancy
potentially reduce risk of vertical transmission
improve retention of care post party

107
Q

What PEP should be given to the NEONATE if VERY LOW or LOW risk of HIV-2 tranmission?

A

ZIDOVUDINE

108
Q

What PEP should be given to the NEONATE if HIGH risk of HIV-2 tranmission?

A
TRIPLE THERAPY:
ZIDOVUDINE
\+
LAMIVUDINE
\+
RALTEGRAVIR
109
Q

What alternative 3rd agent can be used as PEP for neonate at high risk of HIV-2 transmission?

A

LOPINAVIR/ritonavir (with caution)

110
Q

What THREE measures can be used to define HIV-2 treatment failure?

A

1) DETECTABLE viral load (2 consecutive samples)
2) DECLINE CD4 count
3) HIV/AIDS specific symptoms

111
Q

Is PEP and PrEP available for HIV-2?

A

YES
Use same as for HIV-1
No evidence