Testing after possible recent infection

Published: 30 June 2012
  • Many people with recent infection experience symptoms such as fever and rash, and may attend healthcare services.
  • Primary HIV infection is a key opportunity for diagnosis, when motivation to test may be high.
  • Fourth-generation tests are recommended. If recent infection is suspected, but initial results are negative, tests may be repeated one week later.

Prompt diagnosis of people with recent HIV infection (also referred to as acute or primary infection) is important. At this stage of infection, people have high HIV viral load in blood and the genital tract, increasing the probability of onward transmission. Almost by definition, a person with primary HIV infection has recently engaged in a behaviour that led him or her to acquire HIV, and that behaviour may be continuing, as the person is unaware of the infection. Some studies suggest that up to half of new HIV infections may have been passed on from people who themselves were recently infected (and are probably undiagnosed).1 2

A very high viral load usually develops about five days after infection. Symptoms may develop about ten days after infection. These symptoms occur in between 70 and 90% of people during primary HIV infection, and such illness is sometimes referred to as ‘sero-conversion illness’.

A survey of 258 people screened in San Francisco3 for potential primary HIV infection indicated that the following symptoms were more likely to be reported by people who did have primary infection, as compared to people who remained HIV negative:

  • Fever and rash together (8.4 times more likely to occur in people with primary HIV infection).
  • Fever (5.2 times more likely).
  • Rash (4.8 times more likely).
  • Oral ulcers (3.1 times more likely).
  • Joint pain (2.6 times more likely).
  • Sore throat (2.6 times more likely).
  • Loss of appetite (2.5 times more likely).
  • Weight loss of greater than 5lbs (2.5kg) (2.8 times more likely).
  • Muscle pain (2.1 times more likely).
  • Fatigue (2.2 times more likely).
  • Nausea (1.9 times more likely).

Other symptoms such as headaches, night sweats, diarrhoea, ulcers on the genitals and vomiting were just as likely to occur in people who did not have infection. 

In this study, most symptoms lasted for ten days or less, except for genital ulcers which were longer lasting.

Other authorities have suggested that the ‘triad’ of fever, rash and severe sore throat all occurring together should always be considered a potential indicator of possible primary HIV infection.4

Although many individuals with symptoms may seek care from a GP or other health service, the diagnosis is frequently missed due to the short duration of symptoms and their similarity with other illnesses such as glandular fever and other viral infections.5 6 7 8 Not many people with these symptoms request an HIV test.9

Primary HIV infection, especially when there are symptoms, is a key opportunity for diagnosis, when motivation to test may be high. More diagnoses at this time will reduce the proportion of people who are diagnosed late, will allow individuals to start HIV treatment at the most appropriate time and provide an opportunity for individual risk reduction, so reducing onward transmission. 

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  1. Brenner BG et al. High rates of forward transmission events after acute/early HIV-1 infection. J Infect Dis 195: 951-959, 2007
  2. Hughes G et al. Recent phylodynamics of the HIV epidemic among MSM in the UK. Fifteenth Conference on Retroviruses and Opportunistic Infections, Boston, abstract 13, 2008
  3. Hecht FM et al. Use of laboratory tests and clinical symptoms for identification of primary HIV infection. AIDS 16: 1119-1129, 2002
  4. National AIDS Trust Primary HIV Infection. London, 2008
  5. Melzer M et al. HIV infection may also cause rash or glandular fever type illness. British Medical Journal, 326: 552, 2003
  6. Weintrob AC et al. Infrequent diagnosis of primary human immunodeficency virus infection. Missed opportunities in primary care settings. Archives of Internal Medicine 163: 2097-2100, 2003
  7. Sudarshi D et al. Missed opportunities for diagnosing acute seroconversion illness. HIV Med 7 (Supplement 1), abstract 031, 2006
  8. Burns FM et al. Missed opportunities for earlier HIV diagnosis within primary and secondary healthcare settings in the UK. AIDS 22: 115 – 122, 2007
  9. Stekler J et al. Primary HIV infection education. Knowledge and attitudes of HIV-negative men who have sex with men attending a public health sexually transmitted disease clinic. J Acquir Immune Defic Syndr 42: 123-126, 2006
This content was checked for accuracy at the time it was written. It may have been superseded by more recent developments. NAM recommends checking whether this is the most current information when making decisions that may affect your health.
Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap

This content was checked for accuracy at the time it was written. It may have been superseded by more recent developments. NAM recommends checking whether this is the most current information when making decisions that may affect your health.

NAM’s information is intended to support, rather than replace, consultation with a healthcare professional. Talk to your doctor or another member of your healthcare team for advice tailored to your situation.