DISCUSSION:: Will restricting international travel stop a pandemic?

[Laidback Al]

Mingus posted an article in the scientific library about the spread of a pandemic entitled "The Waiting Time for Inter-Country Spread of Pandemic Influenza".

Efforts that reduce the disease reproduction number in the source region below two and severe travel restrictions are most effective for delaying a local epidemic, and under favourable circumstances, could add several months to the delay. On the other hand, the model predicts that border screening for symptomatic infection, wearing a protective mask during travel, promoting early presentation of cases arising among arriving passengers and moderate reduction in travel volumes increase the delay only by a matter of days or weeks.....

Short of preventing international travel altogether, eradicating a nascent pandemic in the source region appears to be the only reliable method of preventing country-to-country spread of a pandemic strain of influenza.

This article clearly indicates that to delay or possibly stop a pandemic in a source country requires that personal contacts be minimized (i.e. limiting transmission by keeping the R0 number low) and that local travel restrictions be implemented. Screening for sick passengers at arrival locations in recipient countries will only prevent the spread of the pandemic by a "matter of days or weeks".

This suggests that an effort should be made to provide potential source countries with financial aid to implement these recommendation to slow the spread of a worldwide pandemic.

 

[Shannon Bennett]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

I am going to think about this overnight but, off the top of my head if you could enforce the restrictions I would have to agree.

 

[4-ABBA]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

I am going to think about this overnight but, off the top of my head if you could enforce the restrictions I would have to agree.

In many poorer countries, food is obtained by going to large open air markets, where the foodstuffs are supplied by many local merchants. If restriction of contacts is a goal, distribution of foodstuffs will have to be rethought from the ground up.

 

[Mingus]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

The article plays with very complex mathematical modelling but the conclusion can easily be summarise in that simple way...

- Try to contain the bug while it is small at the location it first appear...this way you will gain months.
- Try to protect you where you are hidden, the bug will find you anyway with only a couples of days delay.

Am-I too simplistic ? or is this the conclusion ?

Now, try to explain this to the majors airlines company ...
To the G-8 country member...

 

[Laidback Al]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

The article plays with very complex mathematical modelling but the conclusion can easily be summarise in that simple way...

- Try to contain the bug while it is small at the location it first appear...this way you will gain months.
- Try to protect you where you are hidden, the bug will find you anyway with only a couples of days delay.

Am-I too simplistic ? or is this the conclusion ?

Now, try to explain this to the majors airlines company ...
To the G-8 country member...

Very clear and concise summary of the point of the article. Thank you.

 

[Jeremy]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

Personally I believe containment is only possible (if it is possible at all) in a small isolated community with infrequent contact with the commercial world.

I believe that once you have an person with a easily transmiassble form of H5N1 reaching an airport it is already too late.

 

[Mingus]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

Personally I believe containment is only possible (if it is possible at all) in a small isolated community with infrequent contact with the commercial world.

I believe that once you have an person with a easily transmiassble form of H5N1 reaching an airport it is already too late.

So you would like the ports & airports of the first country where major & explosives outbreak ( I mean like more than 100 peoples sicks with medical staff heavily hitten) been shut down as quick as possible ?
I expect at least some days of delay before such heavy decision could be taken from any govt in the world.

 

[Laidback Al]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

Personally I believe containment is only possible (if it is possible at all) in a small isolated community with infrequent contact with the commercial world.

I believe that once you have an person with a easily transmiassble form of H5N1 reaching an airport it is already too late.

I think that the authors of the article would agree with you. The modelling efforts suggests that local restrictions could delay the spread by perhaps several months, not that such efforts would keep it from spreading.

 

[Mingus]

Re: DISCUSSION:: Will restricting international travel stop a pandemic?

All forms of border control are eventually overwhelmed by the cumulative number of infected travelers that attempt to enter the country. The only way to prevent a local epidemic is to rapidly implement local control measures that bring the effective reproduction number in the local area down below 1, or to achieve rapid elimination in the source region, in agreement with other recent studies [6]?[8]. Preventing the exponential growth phase of an epidemic in the source region appears to be the only method able to prevent a nascent influenza pandemic

But the positive tone is that one

Our results are conservative in the sense that they give an upper bound for the probability that an infected traveler manages to initiate an epidemic, compared to an offspring distribution with a greater variance but the same reproduction number [14].
(...)
our results indicate that at-risk countries receiving a reasonably small number of travelers (say 400 per day) from the infected source region can expect a natural delay until importing an epidemic of the order of 2 months.

Wich mean that we may really gain months delay if the initial reaction is strong in the initial country.