A first study has shown how an 动物 society actively reorganizes itself to reduce the spread of 疾病.
Generally speaking, high 人口 density in a geographical region is the biggest factor which contributes to faster spread of a disease. When populations become dense it causes overcrowding which then leads to decline in living conditions. This causes the rate of disease transmission to increase mainly due to frequent and close contacts between individuals. Such populations become breeding grounds for infectious agents like viruses and bacteria.
蚁群
蚂蚁 are organisms which thrive almost everywhere be it 森林 or deserts and they live in large colonies or groups. Ants are known to be very social and this 行为 gives them huge advantage over insects or animals which exist solitary. An ant colony is organized in sub-groups based upon their age and the tasks which each of these groups need to carry out. There are mainly three types of ants in a colony – queen ant, females who are mainly ‘workers’ and males. Their main goal is survival, growth and reproduction. So, ant’s interactions with other colony members are not really random as one would assume. The queen ant is the most important as only it can lay eggs and is the only member of an ant colony who can produce new members. The ‘younger’ ants, also called ‘nurses’ look after the brood at the centre of the colony. While ‘older’ ants act like foragers who travel and collect food from outside and for this reason older ants are more exposed and vulnerable to pathogens. A pathogenic invasion can cause spread of a disease and could likely terminate the entire colony.
在发表的一项研究 科学 表明当致病病原体进入蚁群时，蚂蚁会改变自己的行为，以保护蚁群免受即将发生的流行病的侵袭。 他们保护他们的女王和他们的整个后代免于感染疾病，为此他们开发了一种有趣的“防御机制”。 这种机制的一个重要方面是在殖民地内发生的“社会组织”。 奥地利科学技术研究所和洛桑大学的研究人员通过使用“条形码”系统仔细跟踪和了解正常情况下与疾病传播时蚁群内蚂蚁之间的相互作用进行了这项研究。 他们在大约 2260 只花园蚂蚁上放置了数字标记，红外摄像机每半秒捕捉一次蚁群的图像。 这种方法使他们能够跟踪和测量每个蚂蚁成员的运动和位置，以及它们在蚁群内的社交互动。
蚂蚁的防御机制
To initiate disease transmission, around 10 percent of older ants or foragers were exposed to fungal spores which spread very fast. A comparison of ant colonies before and post pathogen exposure was made. Clearly, ants quickly realized the presence of 真菌 spores and they subdivided themselves into groups and changed their interactions with each other. Nurses only interacted with nurses and foragers with only foragers and their interaction with each other was diminished. The entire colony of ants changed their response, even those ants that were not exposed to fungal spores. This can be seen as a preventive measure as it reduces the risk of disease spread. qPCR technique was used to quantify the number of spores carried by an ant as spores would amplify the targeted DNA molecule. A track was kept on the number of fungal spores. When ants changed their interaction, the pattern of fungal spores also kept changing which was noticeable in the readings.
有趣的是，蚁群保护了可以做出贡献的“重要成员”——蚁后、护士和年轻工人——他们的生存至关重要。 详细的存活实验表明，第一次暴露后 24 小时的任何病原体负荷与疾病死亡直接相关，并且具有很高的相关性。 年龄较大或觅食的蚂蚁的死亡率比护士高，而最有价值的成员——蚁后——活到最后。
这项研究从蚂蚁的角度揭示了疾病的动态，因为它们共同应对疾病传播的可能风险。 它确定了生物体之间的社会相互作用在疾病传播过程中至关重要。 对蚂蚁的研究可以指导我们了解可能与其他社会群体生物相关的过程。 我们需要评估什么会影响疾病风险以及可以设计哪些合适的控制措施。 在考虑免疫学、疾病传播和人口结构等因素的情况下，人口范围的动态势在必行。
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{您可以通过单击下面引用来源列表中给出的 DOI 链接来阅读原始研究论文}
来源（S）
Stroeymeyt N 等。 2018. 社交网络可塑性减少了一种真社会性昆虫的疾病传播。 科学. 362（6417）。 https://doi.org/10.1126/science.aat4793
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