TB Infection Control

Is there a prevailing wind direction? The design sounds good to me, but I might like to see it further from the lab, or any other structure, walkway, etc, depending on prevailing wind direction. Several smoke tube tests might give you a sense of what happens to aerosol generated in the proposed structure.

Ed

Edward A. Nardell, MD
Associate Professor
Harvard Medical School
Harvard School of Public Health

Brigham & Women's Hospital
Division of Global Health Equity
Partners In Health
641 Huntington Ave
3A-03
Boston, MA 02115

432-2080 (academic); 877-9412 (cell)

Thanks alot for the fast reply.
 
We can't really depend on prevailing wind direction, as the facility is found inside heavily built up area with exisitng buildings, fences, vegetation, etc...

we are using in peru one open system to take sputum .we dont neeed or
recomended a close roon .is better more unmy p´lace is enpough to avoid
contamination
best regards
e gotuzzothan 5 mts of any place but very open because the UV of the
regular s

--
************************
Dr. Eduardo Gotuzzo
Director
Instituto de Medicina Tropical
Alexander von Humboldt
UPCH
e-mail:

www.upch.edu.pe/tropicales
www.gorgas.org

Dear all,

It seems OK. But as a patient I will have lot of reservations entering a room where another known TB patient has coughed to produce sputum. This is common in places where a sputum collection room is provided.

I have also seen in a very crowded hospital, a open roof (~ 15 x10 ft) with a 6-7 foot wall all around with a opening on one side. this space is cleaned with water jets periodically to keep the place neat for the patients to use the facility. I see patients use it with less hesitiation. This is simple and easy to maintain even for the hospital staff who is responsible for keeping the place neat and clean.



With regards.


Dr. N. Selvakumar
Scientist - 'G"
Tuberculosis Research Centre (ICMR)
Mayor VR Ramanathan Road
Chetput, Chennai 600 031
India.
Fax: +91 44 2836 2528
Ph (off): +91 44 2836 9620

Dear Merid
It sounds like a good construction- my only concern is that the gap above the wall ( between it and the roof) may change the airflows- but then again- does it matter? Most of our booths have lots of air inlets which is expected to support an up draft towards the gap (as described by you).The smoke tests show the airflows moving up and out.
I don't know if this helps.
Regards
Shaheen

Prof Shaheen Mehtar
MBBS, FRC Path (UK), FCPath (Micro) (SA), MD (Lon)
Chair of Infection Control Africa Network (ICAN)
Head of Academic Unit for Infection Prevention and Control
Tygerberg Hospital &Fac of Health Sciences, Stellenbosch Uni
PO Box 19063,
Tygerberg 7505, Cape Town
Tel: +27 21 938 5051
Fax: + 27 21 938 5065
Mobile: +27 82 852 3697
http://www.sun.ac.za/uipc
Want to know what is happening in Africa in infection control?
Visit Infection Control Africa Network (ICAN)
http://www.ICANetwork.co.za

Dates for your diary!
4th ICAN conference: 26-29th November, 2012, Cape Town

Good discussion, thanks. I would be cautious about using water jets to clean
areas as there may be a risk of generating aerosols. There are some reports
of TB transmission to zoo staff using high pressure water jets to clean
animal enclosures.
Regards,
Helen

Dr Helen Cox
Médecins Sans Frontières
Town One Properties - Site B
Sulani Drive, Khayelitsha
Cape Town, South Africa

Tel +27(0) 21 364 5490
Cell +27 (0)767 169 702
Fax +27 21 361 7051
Email

Hello Merid,
Thanks for your question.
I like the design as described but I will want to ask a few questions before I make some suggestions:
Is this just a sputum booth for 1 facility or you intend to apply this design to several others if this design is successful?
Are you considering the element of cost in design and building this structure so that you want to be cost effective?
Is there privacy in terms of the site identified for this sputum booth on its own i.e. Is it located away from human activity or it is in full view of human activity?
Do the potential users have a reservation about being in enclosed spaces or not?

In the light of these questions why not have a structure that has 2 or 3 enclosed sides with the opened sides catching the prevailing winds as mentioned by Dr Nardell and blowing away from the lab and human activity. I don't think you need a door. Do you need to make the material of the walls of concrete blocks? Why not try steel plates or plastic T & G panels (3 - 4 inch wide plastic sheets about 1/2inch thick ...

Hello Merid,
Thanks for your question.
I like the design as described but I will want to ask a few questions before I make some suggestions:
Is this just a sputum booth for 1 facility or you intend to apply this design to several others if this design is successful?
Are you considering the element of cost in design and building this structure so that you want to be cost effective?
Is there privacy in terms of the site identified for this sputum booth on its own i.e. Is it located away from human activity or it is in full view of human activity?
Do the potential users have a reservation about being in enclosed spaces or not?

In the light of these questions why not have a structure that has 2 or 3 enclosed sides with the opened sides catching the prevailing winds as mentioned by Dr Nardell and blowing away from the lab and human activity. I don't think you need a door. Do you need to make the material of the walls of concrete blocks? Why not try steel plates or plastic T & G panels (3 - 4 inch wide plastic sheets about 1/2inch thick assembled side by side to lock into each other). These are washable as in Peru and can be cleaned all the time. You can maintain the roof which I believe is excellent. The covered walls can face areas of human activity and the open side can face areas of little human activity to ensure patient privacy when they enter. Health workers can also supervise the procedure without getting too close. This structure will look like a sheltered public bus stop in any country but is very effective. We are preparing to introduce such a design in Ghana.
Thanks
--
Dr. Nii Nortey Hanson-Nortey
Deputy Programme Manager
National TB Control Programme
P. O. Box KB 493 Korle Bu
Accra, Ghana
Tel/Fax : +233 30 266 0023
Mobile : + 233 26 238 6666
Email:
Skype: nii.nortey

Go to the people, Live with them, Love them, Learn from them.
Start with what they know. Build with what they know.
But the best of leaders, when their task is accomplished, the work is done;
The people will all say, we have done it ourselves. Lao Tzu

Good information Dr Cox!
--
Dr. Nii Nortey Hanson-Nortey
Deputy Programme Manager
National TB Control Programme
P. O. Box KB 493 Korle Bu
Accra, Ghana
Tel/Fax : +233 30 266 0023
Mobile : + 233 26 238 6666
Email:
Skype: nii.nortey

Go to the people, Live with them, Love them, Learn from them.
Start with what they know. Build with what they know.
But the best of leaders, when their task is accomplished, the work is done;
The people will all say, we have done it ourselves. Lao Tzu

Absolutely, Helen. I was going to not only quote that but also some recent publications relating to dust (from using a broom) and transmission of TB!
Interesting.
s

Prof Shaheen Mehtar
MBBS, FRC Path (UK), FCPath (Micro) (SA), MD (Lon)
Chair of Infection Control Africa Network (ICAN)
Head of Academic Unit for Infection Prevention and Control
Tygerberg Hospital &Fac of Health Sciences, Stellenbosch Uni
PO Box 19063,
Tygerberg 7505, Cape Town
Tel: +27 21 938 5051
Fax: + 27 21 938 5065
Mobile: +27 82 852 3697
http://www.sun.ac.za/uipc
Want to know what is happening in Africa in infection control?
Visit Infection Control Africa Network (ICAN)
http://www.ICANetwork.co.za

Dates for your diary!
4th ICAN conference: 26-29th November, 2012, Cape Town

Hello Nii, Thanks for your elaborate explanation and input.
 
The booth is for one facility only, right now there is also no intention of using this as standard or replicating it elsewhere. But most likely this will happen. The location of the booth in the compound is very private, I can say it is located at dead end, no pass through traffic.
 
Definetly people will like the enclosed one, mainly for the sake of privacy.
 
We will seriously consider your suggestions! Thanks a lot for your time!

Sorry Dr. Mehtar, but it is highly unlikely that sweeping with a broom will generate particles small enough to be inhaled deep into the lungs. Remember, TB is an infection of the aleveolar macrophage - not the upper airways. The water jet that Dr. Cox describes is another matter as high pressure and flows of water can generate particles in the less than 10 micrometer range. Humans are great aerosol generators because when we cough we do generate very high velocities in the central airways, shearing off small droplets (lots of energy required) which can then evaporate into droplet nuclei (1-5 micometers). There is a case reported by CDC of a tuberculosis abscess being cleaned with a water pik which generated aerosol which infected many patients in the vicinity. That was a concentrated source. Even if sweeping could generate respirable particles, the source (dust in rooms) is not likely to be highly concentrated (like a wound). In the Zoo episodes that Dr. Cox mentions, contaminated feces or urine could be a concentrated source, I suppose. There was a report of high velocity jet cleaning of a abattoir resulting in transmission of M. bovis, which I would presume was by the same ...

Sorry Dr. Mehtar, but it is highly unlikely that sweeping with a broom will generate particles small enough to be inhaled deep into the lungs. Remember, TB is an infection of the aleveolar macrophage - not the upper airways. The water jet that Dr. Cox describes is another matter as high pressure and flows of water can generate particles in the less than 10 micrometer range. Humans are great aerosol generators because when we cough we do generate very high velocities in the central airways, shearing off small droplets (lots of energy required) which can then evaporate into droplet nuclei (1-5 micometers). There is a case reported by CDC of a tuberculosis abscess being cleaned with a water pik which generated aerosol which infected many patients in the vicinity. That was a concentrated source. Even if sweeping could generate respirable particles, the source (dust in rooms) is not likely to be highly concentrated (like a wound). In the Zoo episodes that Dr. Cox mentions, contaminated feces or urine could be a concentrated source, I suppose. There was a report of high velocity jet cleaning of a abattoir resulting in transmission of M. bovis, which I would presume was by the same mechanism. To be clear, high velocity jet cleaning is a concern - sweeping is not a concern - for TB transmission.

Ed Nardell

Dear Ed
I knew you would take the bait! I shall send you the published references which I also found most interesting, because I was looking for papers on this subject to handle an internal matter.
I totally agree with the aerosol generation with vapour, both with TB and legionella!
Have a good holiday!
s


Prof Shaheen Mehtar
MBBS, FRC Path (UK), FCPath (Micro) (SA), MD (Lon)
Chair of Infection Control Africa Network (ICAN)
Head of Academic Unit for Infection Prevention and Control
Tygerberg Hospital &Fac of Health Sciences, Stellenbosch Uni
PO Box 19063,
Tygerberg 7505, Cape Town
Tel: +27 21 938 5051
Fax: + 27 21 938 5065
Mobile: +27 82 852 3697
http://www.sun.ac.za/uipc
Want to know what is happening in Africa in infection control?
Visit Infection Control Africa Network (ICAN)
http://www.ICANetwork.co.za

Dates for your diary!
4th ICAN conference: 26-29th November, 2012, Cape Town

It is very difficult to infer that staff already working in zoo got infected and diseased by cleaning rooms with water jet



With regards.


Dr. N. Selvakumar
Scientist - 'G"
Tuberculosis Research Centre (ICMR)
Mayor VR Ramanathan Road
Chetput, Chennai 600 031
India.
Fax: +91 44 2836 2528
Ph (off): +91 44 2836 9620

The design is good in several aspects.

However, the booth can be in a location in a open area not far way from the Out patient departement but at the sametime easily accessable to the patient. It would be desirable to keep the roof open for sun light to take care of the arosols to some extend. Any spit can get dried up. Floor can have grills and so that water will not stagnate.



With regards.


Dr. N. Selvakumar
Scientist - 'G"
Tuberculosis Research Centre (ICMR)
Mayor VR Ramanathan Road
Chetput, Chennai 600 031
India.
Fax: +91 44 2836 2528
Ph (off): +91 44 2836 9620

Can't we just wipe down with water and detergent rather than using a hose? I would think this is more constructive than changing the entire structure, especially if there are good air changes inside
S

Prof Shaheen Mehtar
MBBS, FRC Path (UK), FCPath (Micro) (SA), MD (Lon)
Chair of Infection Control Africa Network (ICAN)
Head of Academic Unit for Infection Prevention and Control
Tygerberg Hospital &Fac of Health Sciences, Stellenbosch Uni
PO Box 19063,
Tygerberg 7505, Cape Town
Tel: +27 21 938 5051
Fax: + 27 21 938 5065
Mobile: +27 82 852 3697
http://www.sun.ac.za/uipc
Want to know what is happening in Africa in infection control?
Visit Infection Control Africa Network (ICAN)
http://www.ICANetwork.co.za

Dates for your diary!
4th ICAN conference: 26-29th November, 2012, Cape Town

It is OK if there is no apparant spit. If one finds open spits then staff would resisit to wipe with a swab or mop.

the model which I saw just requires brick walls/plastic walls on four sides with a opening on one side. the height of the wall can be 7 ft. Natural air and un light will take care of the rest. Floor can be of grills to prevent water stagnation. It is less expensive and setting with less resources can adopt.



With regards.


Dr. N. Selvakumar
Scientist - 'G"
Tuberculosis Research Centre (ICMR)
Mayor VR Ramanathan Road
Chetput, Chennai 600 031
India.
Fax: +91 44 2836 2528
Ph (off): +91 44 2836 9620

Dear All, Thank you very much for all these stream of ideas!

Merid

Hi all,
See below report from the infectious disease email service from earlier this
year.
Cheers,
Helen

TUBERCULOSIS, HUMANS, ELEPHANT - USA: (TENNESSEE) 2009
******************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>

Date: Thu 17 Feb 2011
Source: Reuters [edited]
<http://www.reuters.com/article/2011/02/18/us-elephant-tuberculosis-idUSTRE71H...>


Liz, an African elephant housed at a sanctuary for the animals, was the
source of tuberculosis infections among 8 workers at the refuge, an author
of a report on the 2009 outbreak said on Thursday [17 Feb 2011]. None of the
infected employees at the Hohenwald, Tennessee, sanctuary for old, often
abused, elephants, became ill. The workers were given preventive therapy,
and 54-year-old Liz is in quarantine and undergoing treatment.

A report by The Centers for Disease Control and Prevention [CDC] blamed
pressure-washing of elephant barns for the spread of the tuberculosis
bacteria [_Mycobacterium tuberculosis_], which enters through the lungs,
said Dr. William Shaffner, who helped write the report and is an expert on
infectious diseases at Vanderbilt University in Nashville. "Elephants can
excrete the bacteria through their trunks and even in their feces," which
can become an ...

Hi all,
See below report from the infectious disease email service from earlier this
year.
Cheers,
Helen

TUBERCULOSIS, HUMANS, ELEPHANT - USA: (TENNESSEE) 2009
******************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases <http://www.isid.org>

Date: Thu 17 Feb 2011
Source: Reuters [edited]
<http://www.reuters.com/article/2011/02/18/us-elephant-tuberculosis-idUSTRE71H...>


Liz, an African elephant housed at a sanctuary for the animals, was the
source of tuberculosis infections among 8 workers at the refuge, an author
of a report on the 2009 outbreak said on Thursday [17 Feb 2011]. None of the
infected employees at the Hohenwald, Tennessee, sanctuary for old, often
abused, elephants, became ill. The workers were given preventive therapy,
and 54-year-old Liz is in quarantine and undergoing treatment.

A report by The Centers for Disease Control and Prevention [CDC] blamed
pressure-washing of elephant barns for the spread of the tuberculosis
bacteria [_Mycobacterium tuberculosis_], which enters through the lungs,
said Dr. William Shaffner, who helped write the report and is an expert on
infectious diseases at Vanderbilt University in Nashville. "Elephants can
excrete the bacteria through their trunks and even in their feces," which
can become an aerosol mist when hit by pressurized water, said Shaffner, who
is also president of the sanctuary that is 85 miles South of Nashville.

The mist exposed the workers inside the barn and drifted into an adjacent
administrative building where 3 other employees inhaled it, the report
concluded. This should serve as a warning to handlers that even those with
indirect contact with elephants can be infected, Shaffner said.

An estimated one in 8 captive elephants is infected with tuberculosis, he
said. There are as many as 600 captive elephants in the United States.
Workers at the sanctuary who deal directly with the elephants now wear more
elaborate protective clothing and use lower-pressure hoses to clean the
barns, and steps were taken to seal off vulnerable buildings. The Tennessee
sanctuary was created in 1995 and houses 14 African and Asian elephants
where they can wander on 2700 acres.

While elephants can spread the bacteria among themselves and to humans,
Shaffner said the 1st elephant to get tuberculosis likely got it from an
infected person.

[Byline: Andrew Stern and Greg McCune]

------------------------------


Dr Helen Cox
Médecins Sans Frontières
Town One Properties - Site B
Sulani Drive, Khayelitsha
Cape Town, South Africa

Tel +27(0) 21 364 5490
Cell +27 (0)767 169 702
Fax +27 21 361 7051
Email

That is right. staff would have got infected through many of the soruces from the infected animals. how to conclude that the water jets are the exclusive means of transmission.



With regards.


Dr. N. Selvakumar
Scientist - 'G"
Tuberculosis Research Centre (ICMR)
Mayor VR Ramanathan Road
Chetput, Chennai 600 031
India.
Fax: +91 44 2836 2528
Ph (off): +91 44 2836 9620

Thanks Helen, Elephants also are potent generators of aerosols themselves through their trunks, as our African and Indian colleagues know. I have a paper on another elephant paper; treatment was per rectum, with VERY large suppositories!

Ed

Edward A. Nardell, MD
Associate Professor
Harvard Medical School
Harvard School of Public Health

Brigham & Women's Hospital
Division of Global Health Equity
Partners In Health
641 Huntington Ave
3A-03
Boston, MA 02115

432-2080 (academic); 877-9412 (cell)