It's possible to use viral advertising to do this. The WhastApp messages or videos can be viewed as the traditional TV commercial ads. Obviously the design staff have to have enough marketing skills to create good ads. Then the Sudan people that receives those ads will send them again to their collegues... and so on.

Of course this "adicition" can be use to try to create interesting viral messages. But... keep in mind the risk of boomerang effect.

Thanks for valuable contribution , but the problem in Sudan is that ads are of poor quality still addressing consumers in out of date consumers are not affected and producers are not willing to upgrade standards ,, but I think if they r clever enough they can use whatup as stated by Pere A. Palmer 

it will be effective from my point of view, because new media has a wide range and it exceed the traditional media now a days  

true social media is now controlling marketing in a vigorous way but the problem still stands in Sudan is that its not utilized as efficiently as it should or could be if we compare how European countries do they consider social media a vital tool in marketing moreover there is no research as such in Sudan in this aspect as far as i know , if there is could someone pls share ,, 

You need to partner with a public health organization who will have people who can assist you with this endeavour-including with both generating the content as well as the delivery of targeted messaging to your audience. NB It is important that individuals and or organizations who deliver messaging in this particular space are seen to be legitimate, have expertise and can maintain credibility.

Do you have any links to the World Health Organization (WHO) or a professional organization with a publc health interest?  By the way WHO is one of a number of public health organizations who are active on social media including Twitter.

very nice suggestion Deborah Jean Verran , it will really be useful to link with such organizations i think they will be capable of tailoring the messages in a most useful way ,, thanks a lot,,

https://www.facebook.com/solico.fans?ref=ts&fref=ts

developing countries in general (aside from Sudan) social media is booming especially Tumblr is growing faster than Facebook (based on my results from questionnaires and interviews). also when asked what media tool they turn to before a purchase decision, it was unanimous that they all said through word of mouth and social media. so yes definitely awareness campaigns could be even more effective in developing countries than developed

thanks Sara el deeb i would very much like to read your research could you please post the link if it is available on line.,,

We use social media (Facebook and Twitter) for our social advocacy and community development initiatives. We link with relevant mass media sites/ groups. We get thousands of hits. However, the limitation of penetration is to certain age group, and interest groups. We have to plan many access strategies for penetration into the target group.

https://www.facebook.com/AccessAlliance

https://twitter.com/accessalliance

In Vietnam, healthy food product is one of the biggest concerns among consumers and social networking sites develop dramatically. Hence, using social media to position your brand and increase customer's perception is a good way to entry and expanse your market share. However, most of users live in urban areas so that you might be able to access urban market, not rural one.

From my own experience i think that the gap between marketers as pure marketers and food producers or processors limit the scientific use of social media in this respect ,, producers are already occupied with production and are unaware of such forces on the other hand marketers tailor decisions that are far behind food culture ,, thus socil media gets attention only as a gossip tool , i think more serious applied research should be implemented ,,

Yes, in my opinion social media can be used to create awareness about food products in developing countries. Even if people in some countries are addicted to social media, feeding useful and relevant information will increase its reach to more people. So, users of social media will have to go through the information on food products which otherwise they would not have been exposed to.

Yes. Social media is a very effective method to communicate the various strata of the society. It helps to know both good and bad things. So I do not see any harm in using social media to promote food products among communities because social indifference will determine the market.

I think that a review of studies on use of social media as a tool of advertising,persuasion and Marketing can help  better to answer your query instead of personal opinions based upon our personal existing attitudes regarding Advertiesments and Advertising