NASA-STD-3001 Technical Brief

Relevant Technical 

Requirements

Health Stabilization 

Program (HSP)

OCHMO-TB-006

Rev E

NASA-STD-3001 Volume 1, Rev C

[V1 3002] Pre-Mission Preventive Health 

Care 

[V1 3012] Terrestrial Launch/Landing 

Medical Support 

Executive Summary

A comprehensive Health Stabilization Program (HSP) is 

needed for all spaceflight missions to reduce infections 

pre-flight and prevent subsequent symptoms in-flight. 

Among other considerations, the increased incidence of 

infectious diseases in-flight requires additional resources 

to treat the crew and results in decreased crew 

performance. A HSP has been implemented since the 

Apollo 14 mission and has led to substantial mission 

success. The two biggest components of the HSP are preflight immunizations and quarantine. Through a 

combination of these two factors, in-flight infectious 

diseases (especially upper respiratory and enteric 

infections) can be mitigated. Current NASA/JSC protocol 

mandates the HSP begin 14 days prior to launch. If the 

crew will not be in space for a considerable amount of 

time (e.g., less than 1 day), an extensive HSP may not be 

as critical when compared to a longer-duration mission 

(e.g., Shuttle or ISS). However, physical contact between 

non-HSP and HSP crew must be considered. The HSP can 

only be successful if there is full participation by all inflight physical contacts of the crew.

SpaceX Crew 1 during pre-flight quarantine

Shuttle program health promotion poster

Flight Crew Health Stabilization Program

Clinical Medicine

• Rapid Diagnosis

• Therapy

Immunology

• Serology

• Immunization

Exposure Prevention

• Fomites

• Consumables

• Contacts

Epidemiological 

Surveillance

• Medical History

• Medical Surveillance
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Background

The Physiology of Infectious Disease Transmission

An infection occurs when a virus or bacteria enters the body, multiplies, and causes a reaction (i.e., illness 

or disease). Epidemiologists utilize a three-part model for studying infectious disease and its spread, called 

The Epidemiologic Triad.

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For a disease to spread, there must be:

1. A host that is susceptible to contracting the disease

2. A microbe/pathogen (either viral or bacterial)

3. An environment conducive to disease spread

The Health Stabilization Program 

seeks to protect crewmembers 

by:

a) Quarantine procedures to 

prevent new 

exposure/infection by 

pathogens from potential 

carriers.

b) Ensure if a crewmember has 

been exposed to a pathogen 

and may be in stages 1-3 of 

infection, to bring them back 

to convalescence prior to 

launch.

c) Vaccinate crewmembers and 

close contacts to common 

diseases/illnesses to prevent 

infection if exposed.

The 5 Stages of Infection

1. Incubation – The time from exposure to an infectious agent 

until the onset of symptoms. The incubation time varies 

depending on the disease type (see next page).

2. Prodromal – The time after incubation and before the 

symptoms of disease occur. During this stage, infected 

individuals are capable of transmitting disease to others.

3. Illness – The time at which an infected person presents 

clinical symptoms of a disease/infection.

4. Decline – The time at which the immune system creates a 

successful defense against the pathogen and the number of 

infectious particles decreases, with symptoms gradually 

improving. During this stage, a person is still capable of 

transmitting the pathogen to others.

5. Convalescence – The final stage of infection at which 

symptoms have resolved and individuals are no longer 

contagious and return to normal functioning.
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Background

Health Stabilization Program – Vaccination and Quarantine of Crew and Close Contacts

• Crewmembers and close contacts of crewmembers are required to receive vaccinations for diseases 

identified by medical support personnel to prevent the transmission and infection of illness.

• Crewmembers and close contacts also undergo a quarantine period prior to launch to prevent exposure 

to pathogens and ensure crewmembers are healthy prior to launch. Most illnesses that are not capable 

of being vaccinated against have less than 3 weeks incubation period (see table below).

3

[V1 3002] Pre-Mission Preventive Health Care Pre-mission preventive strategies shall be used to 

reduce in-mission and long-term health medical risks, including, but not limited to:

h. Vaccinations (influenza, tetanus toxoid, varicella zoster vaccine, severe acute respiratory syndrome 

coronavirus 2 (SARS-CoV-2), etc.

k. Pre-mission Health Stabilization Program (HSP) to reduce the likelihood of contracting an infections 

disease before launch.

[V1 3012] Terrestrial Launch/Landing Medical Support All programs shall have medical capability at 

the site of terrestrial launch and landing to address nominal operations and launch/landing 

contingencies, including, but not limited to the following:

a. HSP requirements for the crew, the crew’s family, and supporting personnel for purpose of disease 

prevention.

Disease Incubation Period Contagious Period

Bronchiolitis 4-6 days Onset of cough until 7 days

Colds 2-5 days Onset of runny nose until fever gone

Coughs (viral) 2-5 days Onset of cough until fever gone

Strep Throat 2-5 days Onset of sore throat until at least 12 hours on 

antibiotics and fever gone

Shingles 14-16 days Onset of rash until all sores have crusts

Fifth disease (Erythema 

infectiosum) 4-14 days 7 days before rash until rash begins

Diarrhea (bacterial) 1-5 days Until stools are formed and fever gone

Diarrhea (viral) 1-3 days Until stools are formed and fever gone

Vomiting (viral) 2-5 days Until vomiting stops

Cold sores (herpes) 2-12 days Until cold sores are dry (4-5 days)

Example Incubation and Contagion Period of Common Diseases/Illnesses

Many respiratory infections may also be contagious 2 days prior to symptom onset and thus are difficult to control spread. Table based on 

information from Seattle Children’s Hospital https://www.seattlechildrens.org/conditions/a-z/infection-exposure-questions/

11/30/2023

Rev E
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Background

Pre- and Post-Implementation of an HSP in Apollo Missions

Infectious diseases significantly impacted pre-flight and in-flight phases of Apollo missions 7 – 13. After the 

implementation of a flight crew HSP (FCHSP), a noticeable reduction in illness incidence occurred:

4

Mission Illness Number of Crewmembers 

Involved Mission Phase

Before Implementation of FCHSP

Apollo 7 Upper respiratory infection 3 Preflight, inflight

Apollo 8 Viral gastroenteritis 3 Preflight, inflight

Apollo 9 Upper respiratory infection 3 Preflight, inflight

Apollo 10 Upper respiratory infection 2 Preflight, inflight

Apollo 11 None - -

Apollo 12 Skin infection 2 Inflight

Apollo 13 Rubella 1 Preflight

After Implementation of FCHSP

Apollo 14 - - -

Apollo 15 - - -

Apollo 16 - - -

Apollo 17 Skin infection 1 Preflight

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• Prior to the HSP implementation, 57% of Apollo crewmembers 

experienced some level of infectious illness before flight

• Since Apollo 14, a HSP (featuring quarantines and 

immunizations) has been used before every flight to reduce 

infectious disease risk. While the risk cannot be completely 

eliminated, a comprehensive HSP presents a way to 

significantly reduce hazard

Reference Documents

• SP-368 Biomedical Results of Apollo, Section II: Crew Health and 

Inflight Monitoring

• Biomedical Results of Skylab, Chapter 7: Analysis of the Skylab 

Flight Crew Health Stabilization Plan

• SSP 50480-ANX1 Guidelines and Procedures for the Prevention 

of Infectious Disease Transmission to ISS Crewmembers

• JSC-22538 Flight Crew Health Stabilization Program, Rev. F

Risk of Adverse Health Outcomes and 

Decrements in Performance due to 

Inflight Medical Conditions
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Past and Current HSPs

Apollo

• 21-day HSP for prime and backup crew

• Immunizations

• Diphtheria, Pertussis, Tetanus, Typhoid, Influenza, Mumps, Poliomyelitis, Rubella, Rubeola, Smallpox, and 

Yellow Fever.

• Extensive disease exposure prevention via quarantine

• Limited exposure to fomites, contaminated consumables, and interpersonal contacts

• Crewmembers used different equipment

• Closely controlled living environment – ultra-high efficiency bacterial filters, positive air pressure (outward 

flow of air only), and controlled food and water intake (including microbiological testing of samples)

• No exposure to potential carriers (e.g., children, maintenance personnel); contacts restricted to medically 

approved individuals only (~100 people total)

Skylab

• 21-day pre-flight, 7-day post-flight HSP

• Immunizations similar to Apollo

• Quarantines to minimize crew exposure to infectious diseases; additional space for isolation of an ill crewmember

• Similar to Apollo – positive air pressure

• Primary contacts were inspected by a nurse before interaction with crew; interactions with non-primary 

contacts were performed via closed-circuit television (CCTV). Limitations set on number of primary contacts 

cited as the change that most significantly impacted incidence of disease.

• Food was specially prepared for the crew

Space Shuttle Program

• 7-day pre-flight HSP

• Quarantine facilities were made available 10 days pre-flight if needed for premature isolation

• Limited number of primary contacts, trained to avoid physical contact with crewmembers and heightened 

personal hygiene practices (e.g., hand washing); children <14 years of age restricted

• Pre-visit exams including temperature screening and vaccination requirements

• Maintenance of practices established during Apollo and Skylab, including vaccination and isolation space for 

crewmembers showing signs of illness while in quarantine

• The HSP was largely successful in preventing the occurrence of infectious disease that would affect launch; only 

one Space Shuttle flight was delayed because of infectious disease (respiratory) among the crew

ISS

• 14-day pre-flight HSP

• Countermeasures in place: crew and contact education; hand & respiratory hygiene; physical separation; personal 

protective equipment (PPE); immunizations (similar to Apollo); medical screening of contacts by medical 

personnel before crew interaction; and avoiding tasks with a high risk of infectious disease acquisition

• HSP participants are allowed to have close crew contact, but special guests and VIPs must stay >2 meters away 

and/or wear PPE. Participants are limited to 5 people or family members (with exceptions)

• May be isolated prior to crew contact, depending on when they arrive at the site

• Additional considerations are in place for management of SARS-CoV-2 (COVID-19) risks

Reference Data

5 11/30/2023

Rev E

Risk of Adverse 

Health Event Due To 

Altered Immune 

Response
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Application

Considerations when Implementing an HSP

• Back-up crewmembers, in addition to the prime crew, should be considered in the HSP in the event 

of crew swaps

• The incubation period for almost all non-immunization, preventable infectious diseases is ≤3 weeks

• To ensure minimized risk, isolation/quarantine periods should include at least the 2 weeks 

prior to launch

• Isolation/quarantine periods are reviewed and updated routinely based on evolving risks

• Access to quarantine facilities should only be for mission-required purposes 

• Pertinent modes of transmission for infectious disease prevention include contact, droplet (>5μm), 

airborne (≤5μm), and blood-borne

• HSP Participants

• Any individual who requires access to the quarantine facility for mission-related purposes –

may or may not come into contact with the crew

• Includes operational groups, crew family/personal contacts, special guests & VIPs, aircrew, 

and staff with access to the crew quarters/vehicle

• All participants should be medically screened by physician or medical personnel via 

questionnaires and physical exams before contact with the crew

Immunodeficiency of Deconditioned Crew

• Stress from spaceflight has shown subclinical research findings (findings that can be measured but do 

not require medical intervention) on immune system function.

• NASA continues to monitor immune system function but presently does not provide any additional 

post mission medical care related to the findings.

• NASA continues to ensure that crewmembers receive adequate nutrition, exercise, and behavioral 

health support to minimize the stress of spaceflight.

• Post-flight deconditioned crew care should consider each individual crew member’s personal health 

and relation to stress to determine if additional post mission quarantine measures are needed.

6

Studies have suggested that stress hormone levels are elevated post-flight and correlate with 

mission duration. T cell, natural killer cell, monocyte, and neutrophil function may diminish during 

and/or after spaceflight. 

Source: Makedonas et al. (2020)

Current Immunizations Required for Crew and HSP Participants

Measles Poliomyelitis

Mumps Varicella

Rubella Hepatitis A & B

Diphtheria Influenza

Pertussis

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Rev E
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Back-Up

7 11/30/2023

Rev E
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Rev D  Rev E

• Updated information to reflect the revisions to language throughout both volumes of 

NASA-STD-3001.

• Updated/added website links due to new NASA website launch

Rev C  Rev D

• Added background on disease transmission, vaccinations, and incubation periods

• Updated the relevant technical requirements

Rev B  Rev C

• Added information regarding immunodeficiency of deconditioned crew

Rev A  Rev B

• Updated information to be consistent with NASA-STD-3001 Volume 1 Rev B and 

Volume 2 Rev C.

Original  Rev A

• Reformatting of charts

• Medical screening of contacts by a physician  medical personnel

• Updated Personal Contacts (PCs) to HSP Participants

• Updated requirements for HSP participants (distance and number of participants 

allowed; use of PPE)

• Added statement for management of SARS-CoV-2 (COVID-19) risks

• Added: isolation/quarantine period updates

• Updated Personal Contacts (PCs) to HSP Participants

• Added two immunizations to list [influenza, SARS-CoV-2 (COVID-19)]

• Removed the following statement: “Influenza vaccination is not a requirement; if the 

PC has not received, then they must wear PPE”

Major Changes Between Revisions

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Rev E
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

NASA-STD-3001 Volume 1 Revision C

[V1 3002] Pre-Mission Preventive Health Care Pre-mission preventive strategies shall be used to reduce 

in-mission and long-term health medical risks, including, but not limited to:

a. Optimization of nutrition.

b. Vitamin D supplementation.

c. Assessment of medications needed for in-flight use.

d. Triennial imaging of bone mineral density.

e. Maintenance of optimal aerobic and strength physical fitness.

f. Maintenance of flexibility, agility, and balance.

g. Annual and pre-flight physicals/periodic health evaluations.

h. Preventive dental care.

i. Vaccinations as recommended by CDC and local epidemiological conditions as recommended by 

flight medicine team (e.g., influenza, tetanus toxoid, varicella zoster vaccine, severe acute 

respiratory syndrome (SARS), coronavirus (COVID-19), etc.).

j. Behavioral health and performance training.

k. Flight surgeon monitoring of crewmembers during hazardous training and pre-flight science testing.

l. Total radiation dose control/monitoring.

m. Pre-mission Health-Stabilization Program (HSP) to reduce the likelihood of contracting an infectious 

disease before launch. 

n. Assisted Reproductive Technology (ART) if desired by the crewmember to preserve gametocytes 

prior to missions with exposure to radiation.

[V1 3012] Terrestrial Launch/Landing Medical Support All programs shall have medical capability at the 

site of terrestrial launch and landing to address nominal operations and launch/landing contingencies, 

including, but not limited to the following:

a. HSP technical requirements for the crew, the crew’s family, and supporting personnel for purpose of 

disease prevention.

b. Access to the full spectrum of medical capabilities, from routine medical and behavioral health care 

to advanced trauma life support (ATLS) capabilities, advanced cardiac life support (ACLS), or 

equivalent.

c. Incorporation of civilian and/or Department of Defense (DOD) facilities and Emergency Medical 

Services (EMS).

Referenced Technical Requirements

9

View the current versions of NASA-STD3001 Volume 1 & Volume 2 on the 

OCHMO Standards website

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Rev E
NASA-STD-3001 Technical Brief

OCHMO-TB-006 Health Stabilization Program (HSP)

NASA Office of the Chief Health & Medical Officer (OCHMO)

This Technical Brief is derived from NASA-STD-3001 and is for reference only.

It does not supersede or waive existing Agency, Program, or Contract requirements.

Reference List

1. NASA-STD-3001 Volume 1, Revision A with Change 1. (2015). 

https://www.nasa.gov/sites/default/files/atoms/files/nasa-std-3001-vol-1a-chg1.pdf

2. SP-368 Biomedical Results of Apollo, Section II: Crew Health and Inflight Monitoring. 

https://history.nasa.gov/SP-368/contents.htm

3. Biomedical Results of Skylab, Chapter 7: Analysis of the Skylab Flight Crew Health Stabilization 

Plan. https://lsda.jsc.nasa.gov/books/skylab/biomedical_result_of_skylab.pdf

4. SSP 50480-ANX1 Guidelines and Procedures for the Prevention of Infectious Disease 

Transmission to ISS Crewmembers

5. JSC-22538 Flight Crew Health Stabilization Program, Rev. F

6. Makedonas, G., Mehta, S.K., Scheuring, R.A., Haddon, R., and Crucian, B.E. (2020). SARS-CoV-2 

Pandemic Impacts on NASA Ground Operations to Protect ISS Astronauts. The Journal of Allergy 

and Clinical Immunology: In Practice, 8(10): 3247-3250. 

https://doi.org/10.1016/j.jaip.2020.08.064

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