AIDS window period



OVERVIEW

Definition.

The AIDS window period is the period from when the human immunodeficiency virus (HIV) infects the human body to when markers of infection, such as HIV antibodies, antigens, or nucleic acids in the serum of an infected person can be detected [1].

The window period time for blood transfusion infections is usually 2-8 weeks, and the window period for those infected by sexual intercourse is in the range of 2-3 weeks [2].

Classification

The HIV window period can be categorized into three types of HIV antigen, antibody, and nucleic acid window periods depending on the method of detection [1].

HIV antibody window period: about 3 weeks after infection.

HIV antigen window: about 2 weeks after infection.

Nucleic acid window: about 1 week.

Morbidity

There is no clear data on the incidence of HIV window period, mainly related to the incidence of HIV-infected and AIDS (AIDS) patients.

As of October 2020, there were approximately 1,045,000 people living with HIV and patients with AIDS (HIV/AIDS) in China [3].

By the end of 2021, 38.4 million people were living with HIV infection or AIDS globally, with 1.5 million new HIV infections in that year, of which 28.7 million were receiving antiretroviral therapy [4].

Questions you may be concerned about

Is HIV contagious before the window period?

HIV is contagious before the window period because its contagiousness exists once you are infected with HIV.

The window period of AIDS is mainly the period between HIV infection and the time when antibodies to the virus can be detected, during which time the antibody test results are negative, but the patient is still contagious.

Window period of AIDS patients, the body’s viral load is relatively high, if the patient at this time and others have unclean sex or share injection supplies, the risk of infection is still high.

It is important to take precautionary measures against AIDS in your daily life, avoid sharing injection supplies with others, and avoid unclean sex.

If you suspect that you are infected with HIV, please consult a hospital in time to avoid delays.

Causes

Causes

The basic conditions that lead to infection include the source of infection, the means of transmission, and high-risk groups.

Sources of infection

People infected with HIV and people with AIDS are sources of infection.

HIV is mainly found in body fluids such as blood, semen, vaginal secretions, pleural and abdominal fluid, cerebrospinal fluid, breast milk, and amniotic fluid.

Routes of transmission

HIV cannot be transmitted from the respiratory tract, food, sweat, tears, saliva, cutlery, handshake, sharing office supplies, etc. The specific ways of transmission are as follows.

Sexual contact is the main way of HIV transmission, including unsafe homosexual, heterosexual and bisexual contact, especially male homosexuals are more likely to be infected.

This includes sharing needles for intravenous injections, unregulated interventional medical practices, and tattoos.

Transmission from HIV-infected mothers to their newborns through the placenta, birth canal, and breastfeeding, including intrauterine infection, transmission during labor and delivery, and breastfeeding.

Susceptible Population

The population is generally susceptible.

Male homosexuals, polygamists, intravenous drug users, spouses or sexual partners of HIV-infected persons, and infants of HIV-positive mothers are high-risk groups.

Pathogenesis

HIV mainly attacks CD4+ T-lymphocytes, causing the number of CD4+ T-lymphocytes to decrease continuously, leading to immunodeficiency of the organism, secondary to a variety of opportunistic infections and malignant tumors, etc., and causing corresponding clinical manifestations [5].

In addition, HIV infection also leads to an increased risk of cardiovascular disease, bone disease, nephropathy and hepatic insufficiency.

Symptoms

Main Symptoms

Clinically, HIV is often divided into three phases: acute infection, asymptomatic phase, and AIDS phase, which can be found in the Acquired Immunodeficiency Syndrome entry.

Acute Infectious Stage

The acute phase of infection usually occurs within 6 months of HIV infection.

Most infected patients will have fever, which may be accompanied by sore throat, night sweats, nausea, vomiting, diarrhea, rash, arthralgia, enlarged lymph nodes, and may also have symptoms such as dizziness and headache [6].

Most patients have mild clinical symptoms that last for 1-3 weeks and then resolve on their own.

Asymptomatic phase

This phase may be entered from the acute phase, or directly into this phase without obvious acute phase symptoms.

The duration of this phase is usually 4~8 years. Its duration is related to the number and type of virus infected, the route of infection, the body’s immune status, nutritional conditions and living habits.

In the asymptomatic stage, the immune system is impaired due to the continuous replication of HIV in the infected person’s body, and the count of CD4+ T lymphocytes gradually decreases, and lymph node enlargement may occur.

AIDS stage

The AIDS stage is the final stage of HIV infection.

The main clinical manifestations in this stage are HIV-related symptoms, various opportunistic infections and tumors, such as fever, diarrhea, enlarged lymph nodes, cytomegalovirus infection, Kaposi’s sarcoma, and so on.

Consultation

Department of Medicine

Department of Infectious Diseases

If you have high-risk behaviors for HIV infection, such as unprotected sex, sharing syringes for intravenous drug use, etc., you can consult the Department of Infectious Diseases for further diagnosis.

Fever Clinic

If you are at high risk for HIV infection and have symptoms such as fever, malaise, sore throat, myalgia, anorexia, nausea, etc., you can also consult the Fever Clinic.

Dermatologic and Venereal Disease Clinic

If you suspect that you may be infected with HIV, you can also visit the Dermatology and Venereology Clinic to be tested for HIV and sexually transmitted diseases (STDs).

Preparation

Information on how to register, preparation of documents, and frequently asked questions.

Tips for medical treatment

If you have a fever, you may apply physical cooling measures such as applying ice on the forehead and warm water to the armpits before seeking medical treatment.

Preparation Checklist

Pay particular attention to the time of onset of symptoms, special manifestations, etc.

Is there fever? What is the highest temperature?

Is there diarrhea? How many times a day?

Is there any swelling felt in the neck, groin, etc.? Is the swelling accompanied by pain?

How long have these symptoms been present?

Have you had unprotected sex?

Are there multiple sexual partners?

Is there a history of intravenous drug use?

Does the sexual partner have AIDS?

Test results in the last 1 week that can be carried to the doctor

Laboratory tests: blood test, liver and kidney function, coagulation function, etc.

Imaging tests: chest CT, etc.

Medications used in the last 1 week, if available, bring along the box or package to the doctor

Antipyretic and analgesic medications: ibuprofen, acetaminophen, etc.

Diagnosis

Diagnosis is based on

Medical history

Patients with this condition may have a history of the following

Unsafe sex (including homosexual and heterosexual sexual contact).

History of intravenous drug use.

Children born to HIV-positive individuals.

History of occupational exposure.

Importation of blood or blood products that have not been tested for HIV antibodies.

Clinical manifestations

Most patients have fever, which may be accompanied by sore throat, nausea, vomiting, diarrhea, skin rash, joint pain, and swollen lymph nodes. Most of the patients have mild clinical symptoms, which last for 1~3 weeks and then resolve on their own.

Laboratory Tests

White blood cells, red blood cells, hemoglobin and platelets, lymphocytes may be reduced to varying degrees or normal.

T-lymphocyte subpopulation examination may suggest an inverted CD4/CD8 cell ratio and a progressive decrease in CD4+ T-lymphocytes.

Enzyme-linked immunosorbent assay (ELISA), chemiluminescence, immunofluorescence, rapid tests (spot ELISA and spot immunocolloidal gold or colloidal selenium, immunochromatography, etc.), and simple tests (gelatin particle agglutination test) can be used to detect HIV antibodies as a primary screening test.

If the initial screening test is positive, HIV antibody confirmatory tests (immunoblotting, strip/linear immunoassay and rapid test, etc.) can be performed to confirm the diagnosis of HIV infection.

HIV antibody testing is the gold standard for the diagnosis of HIV infection.Negative HIV antibodies are seen in HIV-uninfected individuals, but screening tests for recently infected individuals in the window period can also be negative [2].

HIV nucleic acid is detected by qualitative or quantitative methods.

HIV can be isolated and cultured by PCR from specimens such as blood, semen, and cerebrospinal fluid, but the procedure is complicated and is currently used only for research.

Differential Diagnosis

If CD4 reduction is present during the window period of HIV, it can be differentiated from primary CD4+ T lymphocytopenia. Those not caused by HIV infection can be differentiated by HIV antigen antibody or nucleic acid testing.

Secondary CD4 cytopenia

Decreased CD4 cell counts can also occur in patients with tumors receiving radiation or chemotherapy, or in patients with organ transplants or autoimmune diseases receiving glucocorticoids or immunosuppressive drugs. It can be differentiated by medical and medication history, or by HIV-related testing.

Treatment

Treatment goals: Maximize suppression of viral replication to reduce viral load to the lower limit of detection and reduce viral mutation; rebuild immune function; reduce abnormal immune activation; reduce transmission of the virus; prevent mother-to-child transmission; reduce the morbidity and mortality of HIV infection and non-AIDS-related diseases; and achieve a normal life expectancy and improve quality of life.

Treatment principle: At present, there is a lack of a cure for AIDS, and comprehensive treatment measures such as antiretroviral and supportive therapy are adopted.

Antiviral treatment

Currently, antiviral drugs mainly include nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), fusion inhibitors (FIs), integrase inhibitors (INSTIs), and co-receptor antagonists, which are often used in combination, all of which need to be administered under the guidance of a doctor.

Nucleoside reverse transcriptase inhibitors

NRTIs selectively bind to HIV reverse transcriptase and inhibit HIV replication and transcription. Common drugs include tenofovir, propofol tenofovir, lamivudine, emtricitabine, azulfidine, zidovudine, and abacavir.

Non-nucleoside reverse transcriptase inhibitors

NNRTIs bind noncompetitively to HIV reverse transcriptase and inhibit HIV replication. Commonly used drugs include efavirenz, nevirapine, rilpivirine, doravirine, and enoxaparin.

Protease inhibitors

Protease inhibitors can effectively prevent the further processing of HIV precursor proteins and inhibit the synthesis of HIV progeny. Commonly used drugs include Lopinavir, Ritonavir, Darunavir, Atazanavir, etc.

Fusion inhibitors

Fusion inhibitors block the fusion of HIV with the cell membrane, thus inhibiting viral replication. Commonly used drugs are Enfuvirtide and Ebovitide.

Integrase inhibitors

Integrase inhibitors block the integration of viral genes into the body’s DNA, thus preventing the creation of a viral reservoir. Commonly used drugs are dolutegravir, bictegravir, raltegravir, and elviravir.

Co-receptor antagonists

Co-receptor antagonists act on the second receptor to mutate its gene, thus preventing the HIV virus from entering the target cells, and at the same time, the body can obtain natural immunity against HIV-1. The most commonly used drug is maraviroc.

Supportive therapy

Patients in the window period of HIV are prone to negative emotions such as low self-esteem, depression, fear, etc. Family members or the society should provide psychological support, and patients can be treated with psychotherapy when necessary.

Interferon, interleukin 2, gammaglobulin and other immunomodulation can be applied to help rebuild the immune function when necessary [7-9].

Various opportunistic infections or tumors secondary to AIDS in the later stages of the disease require appropriate anti-infection or anti-tumor therapy.

Prognosis

Cure

There is no cure for AIDS; if detected and treated early in the window period of AIDS, progression to AIDS stage can be delayed and normal life expectancy may be achieved [10].

After antiretroviral therapy, the vast majority of patients with HIV/AIDS have their immune abnormalities gradually restored to normal or near-normal levels, i.e., immune function is rebuilt. 10-20% of patients have poorly rebuilt immune function and are at increased risk of opportunistic infections.

Patients who enter the AIDS stage may die within 2 years if they are not given effective antiretroviral therapy.

Infection in infants and young children due to mother-to-child transmission progresses more rapidly, and most die within 1 to 5 years if left untreated.

The life expectancy of people infected with HIV through the intravenous route of drug addiction is shorter than that of people infected by other routes.

Hazards

The window stage of HIV can progress to AIDS stage and there can be severe disruption of immune function leading to an increased risk of contracting other diseases such as tuberculosis, Pneumocystis carinii pneumonia, Toxoplasma gondii encephalitis, cryptococcal meningitis, cytomegalovirus retinitis, Kaposi’s sarcoma, and lymphoma to name a few, which can affect life expectancy.

AIDS patients who inadvertently transmit the virus to others may infect them with HIV or develop AIDS, jeopardizing the health of others.

Daily

Daily Management

Diet

There are no special dietary requirements, just follow the principle of “variety, small amount and balance”.

High-protein foods: High-protein foods include fish and shrimp, poultry, soybean products, dairy products, etc. However, a high-protein diet will increase the risk of kidney disease. However, a high protein diet will increase the burden on the kidneys. If you are not feeling well, please contact your doctor or dietitian for appropriate dietary adjustments.

Supplement vitamins and minerals: You should eat more fresh fruits and vegetables, especially foods rich in carotene (e.g. sweet potatoes, pumpkin, carrots), vitamin C (e.g. oranges, broccoli), vitamin E (e.g. pine nuts, pistachio nuts), and zinc-containing foods (e.g. oysters, shellfish, cereals).

Avoid raw, cold, greasy and unbalanced nutrition: raw, cold and greasy food will easily cause diarrhea and affect the absorption rate of food; avoid skipping breakfast, partiality and overeating, which will result in unbalanced nutrition and affect the immune function.

Life management

Do not share personal items that can easily come into contact with blood, such as manual razors, nail clippers and toothbrushes.

Disinfect personal items that have come into contact with blood or body fluids after use by boiling (100°C) for 20 minutes or soaking in 70% alcohol (medical alcohol) to inactivate the virus.

Having a regular sexual partner who is aware of the disease allows for psychological and behavioral precautions to be taken. Use condoms throughout sexual intercourse and do not take any chances.

Spouses should go to the hospital regularly for screening and timely treatment if they are infected with HIV.

Maintain a good mindset, positive treatment, and do not give up on yourself.

Family members should provide patients with care in life and spiritual encouragement, and avoid discrimination.

Inform medical personnel clearly about HIV when seeking medical treatment, especially before blood sampling, gastroscopy, enteroscopy, vaginal examination, anal examination, dental scaling, tooth extraction and other examinations or treatments, so as to avoid spreading the infection to others.

It is strictly prohibited to donate blood, sperm or organs that can be transmitted to others.

Prevention

There is no effective vaccine to prevent AIDS. The main way to prevent AIDS is to cut off the transmission channels, and if there is a risk of exposure, you can use drugs to prevent it.

Cutting off the means of transmission

Set up a healthy concept of sex, use condoms correctly and practice safe sex.

Do not use drugs or share intravenous needles.

HIV-infected persons or patients should inform their sexual partners and not share personal items such as razors.

HIV-infected persons or patients should avoid organ and blood donation.

Control mother-to-child transmission.

Strengthen hospital management, strictly implement the sterilization system, and control hospital cross-infection.

Prevent occupational exposure and infection.

Pre-exposure prophylaxis

For people at high risk of HIV infection, such as sex workers and multiple sex partners, they can reduce the chance of being infected by taking medication in advance under the premise of informed consent and high compliance, and the medication should be applied under the guidance of a doctor.

Post-exposure prophylaxis

People who are not yet infected with HIV, after being exposed to a high risk of infection, such as clear contact with HIV-infected people or people whose infection status is unknown, can use measures such as washing the contaminated area with soapy water and running water, disinfecting the wound, and squeezing out the blood from the wound to the distal end.

At the same time, reduce the risk of HIV infection by taking a continuous course of HIV post-exposure blocking medication for 4 weeks for as short a time as possible, no more than 72 hours.